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In [[mathematics]], the '''spectral theory of ordinary differential equations''' is the part of [[spectral theory]] concerned with the determination of the [[Spectrum_of_an_operator#Spectrum_of_unbounded_operators|spectrum]] and [[eigenfunction|eigenfunction expansion]] associated with a linear [[ordinary differential equation]]. In his dissertation [[Hermann Weyl]] generalized the classical [[Sturm–Liouville theory]] on a finite [[closed interval]] to second order [[differential operator]]s with singularities at the endpoints of the interval, possibly semi-infinite or infinite. Unlike the classical case, the spectrum may no longer consist of just a countable set of eigenvalues, but may also contain a continuous part. In this case the eigenfunction expansion involves an integral over the continuous part with respect to a [[spectral theory|spectral measure]], given by the [[E. C. Titchmarsh|Titchmarsh]]–[[Kunihiko Kodaira|Kodaira]] [[Titchmarsh-Kodaira formula|formula]]. The theory was put in its final simplified form for singular differential equations of even degree by Kodaira and others, using [[John von Neumann|von Neumann]]'s [[spectral theorem]]. It has had important applications in [[quantum mechanics]], [[operator theory]] and [[harmonic analysis]] on [[semisimple Lie group]]s. | |||
==Introduction== | |||
[[Spectral theory]] for second order ordinary differential equations on a compact interval was developed by [[Jacques Charles François Sturm]] and [[Joseph Liouville]] in the nineteenth century and is now known as [[Sturm–Liouville theory]]. In modern language it is an application of the [[spectral theorem]] for [[compact operator]]s due to [[David Hilbert]]. In his dissertation, published in 1910, [[Hermann Weyl]] extended this theory to second order ordinary differential equations with | |||
[[singularity (mathematics)|singularities]] at the endpoints of the interval, now allowed to be infinite or semi-infinite. He simultaneously developed a spectral theory adapted to these special operators and introduced [[boundary condition]]s in terms of his celebrated dichotomy between ''limit points'' and ''limit circles''. | |||
In the 1920s [[John von Neumann]] established a general spectral theorem for [[unbounded operator|unbounded]] [[self-adjoint operator]]s, which [[Kunihiko Kodaira]] used to streamline Weyl's method. Kodaira also generalised Weyl's method to singular ordinary differential equations of even order and obtained a simple formula for the [[spectral theorem|spectral measure]]. The same formula had also been obtained independently by [[E. C. Titchmarsh]] in 1946 (scientific communication between [[Japan]] and the [[United Kingdom]] had been interrupted by [[World War II]]). Titchmarsh had followed the method of the German mathematician [[Emil Hilb]], who derived the eigenfunction expansions using [[complex function theory]] instead of [[operator theory]]. Other methods avoiding the spectral theorem were later developed independently by Levitan, Levinson and Yoshida, who used the fact that the [[spectral theorem|resolvent]] of the singular differential operator could be approximated by [[compact operator|compact]] resolvents corresponding to [[Sturm–Liouville problem]]s for proper subintervals. Another method was found by [[Mark Grigoryevich Krein]]; his use of ''direction functionals'' was subsequently generalised by I. M. Glazman to arbitrary ordinary differential equations of even order. | |||
Weyl applied his theory to [[Carl Friedrich Gauss]]'s [[hypergeometric differential equation]], thus obtaining a far-reaching generalisation of the transform formula of [[Gustav Ferdinand Mehler]] (1881) for the [[Legendre function|Legendre differential equation]], rediscovered by the Russian physicist [[Vladimir Fock]] in 1943, and usually called the '''[[Mehler–Fock transform]]'''. The corresponding ordinary differential operator is the radial part of the [[Laplacian operator]] on 2-dimensional [[hyperbolic space]]. More generally, the [[Plancherel theorem]] for [[SL(2,R)]] of [[Harish Chandra]] and [[I. M. Gelfand|Gelfand]]–[[M. A. Naimark|Naimark]] can be deduced from Weyl's theory for the hypergeometric equation, as can the theory of [[Zonal spherical function|spherical function]]s for the [[isometry group]]s of higher dimensional hyperbolic spaces. Harish Chandra's later development of the Plancherel theorem for general real [[semisimple Lie group]]s was strongly influenced by the methods Weyl developed for eigenfunction expansions associated with singular ordinary differential equations. Equally importantly the theory also laid the mathematical foundations for the analysis of the [[Schrödinger equation]] and [[scattering matrix]] in [[quantum mechanics]]. | |||
== | == Solutions of ordinary differential equations == | ||
{{Main|Ordinary differential equations}} | |||
=== Reduction to standard form === | |||
Let ''D'' be the second order differential operator on ''(a,b)'' given by | |||
= | :<math> Df(x) = -p(x) f^{\prime\prime}(x) +r(x) f^\prime(x) + q(x) f(x),</math> | ||
where ''p'' is a strictly positive continuously differentiable function and ''q'' and ''r'' are continuous | |||
real-valued functions. | |||
For ''x''<sub>0</sub> in (''a'', ''b''), define the [[Sturm–Liouville theory|Liouville transformation]] ψ by | |||
:<math> \psi(x)= \int_{x_0}^x p(t)^{-1/2}\, dt</math> | |||
== | Let ''U'' be the [[unitary operator]] | ||
(''Uf'')·ψ ψ'<sup>½</sup> = ''f'' from ''L''<sup>2</sup> (''a'',''b'') onto | |||
''L''<sup>2</sup>(''c'',''d''), where ''c'' = ψ(''a'') and ''d'' = ψ(''b''). Then | |||
:<math> UDU^{-1} g= -g^{\prime\prime} + R g^{\prime} + Q g,</math> | |||
where ''Q''·ψ = ''q'' and ''R''·ψ= (''p' ''/2 + ''r'')/''p''<sup>½</sup>. | |||
The term in ''g' '' can be removed using an [[Euler]] [[integrating factor]]. If ''S' ''/''S'' = −''R''/2, then ''h'' = ''Sg'' | |||
satisfies | |||
:<math> (S UDU^{-1} S^{-1}) h = -h^{\prime \prime} + V h,</math> | |||
== | where the [[potential]] ''V'' is given by ''V'' = ''Q'' + ''S''<sup>2</sup>/2 + ''S' ''/2. | ||
The differential operator can thus always be reduced to one of the form <ref>{{harvnb|Titchmarsh|1962|p= 22}}</ref> | |||
:<math>Df = - f^{\prime\prime} + qf.</math> | |||
== | ===Existence theorem=== | ||
The following is a version of the classical [[Picard–Lindelöf theorem|Picard existence theorem]] for second order differential equations with values in a | |||
[[Banach space]] '''E'''.<ref>{{harvnb|Dieudonné |1969}}, Chapter X.</ref> | |||
Let α, β be arbitrary elements of '''E''', ''A'' a [[bounded operator]] on ''E'' and ''q'' a continuous function on [''a'',''b'']. | |||
= | Then, for ''c'' = ''a'' or ''b'', | ||
the differential equation | |||
:''Df'' = ''Af'' | |||
has a unique solution ''f'' in ''C''<sup>2</sup>([''a'',''b''],'''E''') satisfying the initial conditions | |||
:''f''(''c'') = β, ''f'' '(''c'') = α. | |||
In fact a solution of the differential equation with these initial conditions is equivalent to a solution | |||
of the [[integral equation]] | |||
:''f'' = ''h'' + ''T'' ''f'' | |||
with ''T'' the bounded linear map on ''C''([''a'',''b''], '''E''') defined by | |||
:<math> Tf(x) = \int_c^x K(x,y)f(y) \, dy,</math> | |||
where ''K'' is the [[Volterra kernel]] | |||
:''K''(''x'',''t'')= (''x'' − ''t'')(''q''(''t'') − ''A'') | |||
and | |||
:''h''(''x'') = α(''x'' − ''c'') + β. | |||
Since ||''T''<sup>k</sup>|| tends to 0, this integral equation has a unique solution given by the [[Neumann series]] | |||
:''f'' = (''I'' − ''T'')<sup>−1</sup> ''h'' = ''h'' + ''T'' ''h'' + ''T''<sup>2</sup> ''h'' + ''T''<sup>3</sup> ''h'' + ··· | |||
This iterative scheme is often called ''Picard iteration'' after the French mathematician [[Charles Émile Picard]]. | |||
===Fundamental eigenfunctions=== | |||
If ''f'' is twice continuously differentiable (i.e. ''C''<sup>2</sup>) on (''a'', ''b'') satisfying ''Df'' = λ''f'', then ''f'' is called an [[eigenfunction]] of ''L'' with [[eigenvalue]] λ. | |||
* In the case of a compact interval [''a'', ''b''] and ''q'' continuous on [''a'', ''b''], the existence theorem implies that for ''c'' = ''a'' or ''b'' and every complex number λ there a unique ''C''<sup>2</sup> eigenfunction ''f''<sub>λ</sub> on [''a'', ''b''] with ''f''<sub>λ</sub>(c) and ''f'' '<sub>λ</sub>(c) prescribed. Moreover, for each ''x'' in [''a'', ''b''], ''f''<sub>λ</sub>(x) and ''f'' '<sub>λ</sub>(x) are [[holomorphic function]]s of λ. | |||
* For an arbitrary interval (''a'',''b'') and ''q'' continuous on (''a'', ''b''), the existence theorem implies that for ''c'' in (''a'', ''b'') and every complex number λ there a unique ''C''<sup>2</sup> eigenfunction ''f''<sub>λ</sub> on (''a'', ''b'') with ''f''<sub>λ</sub>(c) and ''f'' '<sub>λ</sub>(c) prescribed. Moreover, for each ''x'' in (''a'', ''b''), ''f''<sub>λ</sub>(x) and ''f'' '<sub>λ</sub>(x) are [[holomorphic function]]s of λ. | |||
===Green's formula=== | |||
If ''f'' and ''g'' are ''C''<sup>2</sup> functions on (''a'', ''b''), the [[Wronskian]] ''W''(''f'', ''g'') is defined by | |||
:''W''(''f'', ''g'') (x) = ''f''(''x'') ''g'' '(''x'') − ''f'' '(''x'') ''g''(''x''). | |||
[[Green's formula]]{{disambiguation needed|date=July 2012}} states that for ''x'', ''y'' in (''a'', ''b'') | |||
:<math> \int_x^y (Df) g - f (Dg) \, dt = W(f,g)(y) - W(f,g)(x).</math> | |||
When ''q'' is continuous and ''f'', ''g'' ''C''<sup>2</sup> on the compact interval [''a'', ''b''], this formula also holds for ''x'' = ''a'' or ''y'' = ''b''. | |||
When ''f'' and ''g'' are eigenfunctions for the same eigenvalue, then | |||
:<math> {d\over dx} W(f,g) =0, </math> | |||
so that ''W''(''f'', ''g'') is independent of ''x''. | |||
== Classical Sturm–Liouville theory == | |||
{{Main|Sturm–Liouville theory}} | |||
Let [''a'', ''b''] be a finite closed interval, ''q'' a real-valued continuous function on [''a'', ''b''] and let ''H''<sub>0</sub> be the | |||
space of C<sup>2</sup> functions ''f'' on [''a'', ''b''] satisfying the mixed [[boundary condition]]s | |||
:<math> \cos \alpha \,f(a) - \sin \alpha \,f^\prime(a)=0, \qquad \cos\beta \,f(b) - \sin \beta\, f^\prime(b)=0,</math> | |||
with [[inner product]] | |||
:<math> (f,g) = \int_a^b f(x) \overline{g(x)} \, dx.</math> | |||
In practise usually one of the two unmixed boundary conditions: | |||
*[[Dirichlet boundary condition]] ''f''(''c'') = 0 | |||
*[[Neumann boundary condition]] ''f'' '(''c'') = 0 | |||
is imposed at each endpoint ''c'' = ''a'', ''b''. | |||
The differential operator ''D'' given by | |||
:<math> Df=-f^{\prime\prime} + qf </math> | |||
acts on ''H''<sub>0</sub>. A function ''f'' in ''H''<sub>0</sub> is called an [[eigenfunction]] of ''D'' (for the above choice of boundary values) if ''Df'' = λ ''f'' for some complex number λ, the corresponding [[eigenvalue]]. | |||
By Green's formula, ''D'' is formally [[self-adjoint]] on ''H''<sub>0</sub>: | |||
:(''Df'', ''g'') = (''f'', ''Dg'') for ''f'', ''g'' in ''H''<sub>0</sub>. | |||
As a consequence, exactly as for a [[hermitian matrix|self-adjoint matrix]] in finite dimensions, | |||
*the eigenvalues of ''D'' are real; | |||
*the [[eigenspace]]s for distinct eigenvalues are [[orthogonal]]. | |||
It turns out that the eigenvalues can be described by the [[Courant minimax principle|maximum-minimum]] principle of [[John Strutt, 3rd Baron Rayleigh|Rayleigh]]–[[Walter Ritz|Ritz]] <ref>{{harvnb|Courant | Hilbert |1989}}</ref> (see below). In fact it is easy to see ''a priori'' that the eigenvalues are bounded below because the operator ''D'' is itself ''bounded below'' on ''H''<sub>0</sub>: | |||
:*<math>(Df, f) \ge M (f, f)</math> for some finite constant <math>M</math>. | |||
In fact integrating by parts | |||
::<math> (Df,f)= [-f^\prime \overline{f}]_a^b + \int |f^\prime|^2 + \int q |f|^2.</math> | |||
For unmixed boundary conditions, the first term vanishes and the inequality holds with ''M'' = inf ''q''. | |||
In the mixed case the first term can be estimated using an elementary ''Peter-Paul'' version of [[Sobolev inequality|Sobolev's inequality]]: | |||
:: "''Given ε > 0, there is constant R >0 such that |f(x)|''</sub><sup>2</sup> ≤ ε ''(f', f') + R (f, f) for all f in C<sup>1</sup>[a, b].''" | |||
In fact, since | |||
::|''f''(''b'') − ''f''(''x'')| ≤ (''b'' − ''a'')<sup>½</sup>·||''f'' '||<sub>2</sub>, | |||
only an estimate for ''f''(''b'') is needed and this follows by replacing ''f''(''x'') in the above inequality by (''x'' − ''a'')<sup>''n''</sup>·(''b'' − ''a'')<sup>−''n''</sup>·''f''(''x'') for ''n'' sufficiently large. | |||
=== Green's function (regular case) === | |||
From the theory of ordinary differential equations, there are unique fundamental eigenfunctions φ<sub>λ</sub>(x), χ<sub>λ</sub>(x) such that | |||
* ''D'' φ<sub>λ</sub> = λ φ<sub>λ</sub>, φ<sub>λ</sub>(''a'') = sin α, φ<sub>λ</sub>'(''a'') = cos α | |||
* ''D'' χ<sub>λ</sub> = λ χ<sub>λ</sub>, χ<sub>λ</sub>(''b'') = sin β, χ<sub>λ</sub>'(''b'') = cos β | |||
which at each point, together with their first derivatives, depend holomorphically on λ. Let | |||
:ω(λ) = W(φ<sub>λ</sub>, χ<sub>λ</sub>), | |||
an [[entire function|entire holomorphic function]]. | |||
This function ω(λ) plays the rôle of the [[characteristic polynomial]] of ''D''. Indeed the uniqueness of the fundamental eigenfunctions implies that its zeros are precisely the eigenvalues of ''D'' and that each non-zero eigenspace is one-dimensional. In particular there are at most countably many eigenvalues of ''D'' and, if there are infinitely many, they must tend to infinity. It turns out that the zeros of ω(λ) also have mutilplicity one (see below). | |||
If λ is not an eigenvalue of ''D'' on ''H''<sub>0</sub>, define the [[Green's function]] by | |||
:''G''<sub>λ</sub>(''x'',''y'') = φ<sub>λ</sub> (''x'') χ<sub>λ</sub>(''y'') / ω(λ) for ''x'' ≥ ''y'' and χ<sub>λ</sub>(''x'') φ<sub>λ</sub> (''y'') / ω(λ) for ''y'' ≥ ''x''. | |||
This kernel defines an operator on the inner product space C[''a'',''b''] via | |||
:<math> (G_\lambda f)(x) =\int_a^b G_\lambda(x,y) f(y)\, dy.</math> | |||
Since ''G''<sub>λ</sub>(''x'',''y'') is continuous on [''a'', ''b''] x [''a'', ''b''], it defines a [[Hilbert–Schmidt operator]] on the Hilbert space completion | |||
''H'' of C[''a'', ''b''] = ''H''<sub>1</sub> (or equivalently of the dense subspace ''H''<sub>0</sub>), taking values in ''H''<sub>1</sub>. This operator carries ''H''<sub>1</sub> into ''H''<sub>0</sub>. When λ is real, ''G''<sub>λ</sub>(''x'',''y'') = ''G''<sub>λ</sub>(''y'',''x'') is also real, so defines a self-adjoint operator on ''H''. Moreover | |||
* ''G''<sub>λ</sub> (''D'' − λ) =I on ''H''<sub>0</sub> | |||
* ''G''<sub>λ</sub> carries ''H''<sub>1</sub> into ''H''<sub>0</sub>, and (''D'' − λ) ''G''<sub>λ</sub> = I on ''H''<sub>1</sub>. | |||
Thus the operator ''G''<sub>λ</sub> can be identified with the [[Resolvent formalism|resolvent]] (''D'' − λ)<sup>−1</sup>. | |||
=== Spectral theorem === | |||
'''Theorem.''' ''The eigenvalues of D are real of multiplicity one and form an increasing sequence λ<sub>1</sub> < λ<sub>2</sub> < ··· tending to infinity.'' | |||
''The corresponding normalised eigenfunctions form an orthonormal basis of'' ''H''<sub>0</sub>. | |||
''The kth eigenvalue of D is given by the [[Courant minimax principle|minimax principle]]'' | |||
:<math> \lambda_k = \max_{{\rm dim} \, G = k-1} \, \min_{f\perp G} {(Df,f)\over (f,f)}. </math> | |||
''In particular if q<sub>1</sub> ≤ q<sub>2</sub>, then'' | |||
:<math> \lambda_k(D_1) \le \lambda_k(D_2).</math> | |||
In fact let ''T'' = ''G''<sub>λ</sub> for λ large and negative. Then ''T'' defines a [[compact operator|compact self-adjoint operator]] on the Hilbert space ''H''. | |||
By the [[spectral theorem]] for compact self-adjoint operators, ''H'' has an orthonormal basis consisting of eigenvectors ψ<sub>''n''</sub> of ''T'' with | |||
''T''ψ<sub>''n''</sub> = μ<sub>''n''</sub> ψ<sub>''n''</sub>, where μ<sub>''n''</sub> tends to zero. The range of ''T'' contains ''H''<sub>0</sub> so is dense. Hence 0 is not an eigenvector of ''T''. The resolvent properties of ''T'' imply that ψ<sub>''n''</sub> lies in ''H''<sub>0</sub> and that | |||
:''D'' ψ<sub>''n''</sub> = (λ + 1/μ<sub>''n''</sub>) ψ<sub>''n''</sub> | |||
The minimax principle follows because if | |||
:<math>\lambda(G) = \min_{f\perp G} {(Df,f)\over (f,f)},</math> | |||
then λ(''G'')= λ<sub>k</sub> for the [[linear span]] of the first ''k'' − 1 eigenfunctions. For any other (''k'' − 1)-dimensional subspace ''G'', some ''f'' in the linear span of the first ''k'' eigenvectors must be orthogonal to ''G''. Hence λ(''G'') ≤ (''Df'',''f'')/(''f'',''f'') ≤ λ<sub>k</sub>. | |||
=== Wronskian as a Fredholm determinant === | |||
For simplicity, suppose that ''m'' ≤ ''q''(''x'') ≤ ''M'' on [0,π] with Dirichlet boundary conditions. | |||
The minimax principle shows that | |||
:<math> n^2 + m \le \lambda_n(D) \le n^2 + M. </math> | |||
It follows that the resolvent (''D'' − λ)<sup>−1</sup> is a [[trace-class operator]] | |||
whenever λ is not an eigenvalue of ''D'' and hence that the [[Fredholm determinant]] | |||
det I − μ(''D'' − λ)<sup>−1</sup> is defined. | |||
The Dirichlet boundary conditions imply that | |||
:ω(λ)= φ<sub>λ</sub>(''b''). | |||
Using Picard iteration, Titchmarsh showed that φ<sub>λ</sub>(''b''), and hence ω(λ), | |||
is an [[entire function|entire function of finite order]] 1/2: | |||
:ω(λ) = O(e<sup>√|λ|</sup>) | |||
At a zero μ of ω(λ), | |||
φ<sub>μ</sub>(''b'') = 0. Moreover | |||
:<math>\psi(x)=\partial_\lambda \varphi_\lambda(x)|_{\lambda=\mu}</math> | |||
satisfies (''D'' − μ)ψ = φ<sub>μ</sub>. Thus | |||
:ω(λ) = (λ − μ)ψ(''b'') + O( (λ − μ)<sup>2</sup>). | |||
This implies that<ref>{{harvnb|Titchmarsh|1962}}</ref> | |||
* μ is a simple zero of ω(λ). | |||
For otherwise ψ(''b'') = 0, so that ψ would have to lie in ''H''<sub>0</sub>. | |||
But then | |||
:(φ<sub>μ</sub>, φ<sub>μ</sub>) = ((''D'' − μ)ψ, φ<sub>μ</sub>) = (ψ, (''D'' − μ)φ<sub>μ</sub>) = 0, | |||
a contradiction. | |||
On the other hand the distribution of the zeros of the entire function | |||
ω(λ) is already known from the minimax principle. | |||
By the [[Hadamard factorization theorem]], it follows | |||
that<ref>{{citation|last=Titchmarsh|first= E.C.| year=1939| title=Theory of Functions|publisher= Oxford University Press}}, §8.2.</ref> | |||
*<math> \omega(\lambda) = C \prod (1 -\lambda/\lambda_n),</math> | |||
for some non-zero constant ''C''. | |||
Hence | |||
:<math> {\rm det} \,( I - \mu(D - \lambda)^{-1}) = \prod \left( 1 - {\mu \over \lambda_n -\lambda}\right) = \prod {1 - (\lambda+\mu)/\lambda_n \over 1-\lambda/\lambda_n} = {\omega(\lambda+\mu)\over \omega(\lambda)} .</math> | |||
In particular if 0 is not an eigenvalue of ''D'' | |||
:<math>\omega(\mu) = \omega(0) \cdot {\rm det} \,( I - \mu D^{-1}) . </math> | |||
== Tools from abstract spectral theory == | |||
=== Functions of bounded variation === | |||
{{See also|Bounded variation|Lebesgue–Stieltjes integration|Riesz representation theorem}} | |||
A function ρ(''x'') of [[bounded variation]]<ref>{{citation|first=J.C.|last=Burkill|year=1951|title=The Lebesgue Integral|series=Cambridge Tracts in Mathematics and Mathematical Physics|volume=40|publisher=Cambridge University Press| | |||
isbn=0-521-04382-4|pages= 50–52}}</ref> on a closed interval [''a'', ''b''] is a complex-valued function such that | |||
its [[total variation]] ''V''(ρ), the [[supremum]] | |||
of the variations | |||
:<math> \sum_{r=0}^{k-1} |\rho(x_{r+1}) - \rho(x_r)|</math> | |||
over all [[partition of an interval|dissection]]s | |||
:<math> a= x_0 < x_1 < \dots < x_k =b </math> | |||
is finite. The real and imaginary parts of ρ are real-valued functions of bounded variation. If ρ is real-valued and normalised so that ρ(a)=0, | |||
it has a canonical decomposition as the difference of two bounded non-decreasing functions: | |||
:<math> \rho(x) = \rho_+(x) - \rho_-(x),</math> | |||
where ρ<sub>+</sub>(''x'') and ρ<sub>–</sub>(''x'') are the total positive and negative variation of ρ over [''a'', ''x'']. | |||
If ''f'' is a continuous function on [''a'', ''b''] its [[Riemann–Stieltjes integral]] with respect to ρ | |||
:<math>\int_a^b f(x)\, d\rho(x)</math> | |||
is defined to be the limit of approximating sums | |||
:<math>\sum_{r=0}^{k-1} f(x_r)(\rho(x_{r+1})-\rho(x_r))</math> | |||
as the [[partition of an interval|mesh]] of the dissection, given by sup |''x''<sub>''r''+1</sub> - ''x''<sub>''r''</sub>|, tends to zero. | |||
This integral satisfies | |||
:<math>\left|\int_a^b f(x)\, d\rho(x)\right|\le V(\rho)\cdot \|f\|_\infty</math> | |||
and thus defines a [[bounded linear functional]] ''d''ρ on ''C''[''a'', ''b''] with [[norm (mathematics)|norm]] ||d''ρ||=''V''(ρ). | |||
Every bounded linear functional μ on ''C''[''a'', ''b''] has an [[absolute value]] |μ| defined for non-negative ''f'' by<ref>{{citation|first=Lynn H.|last=Loomis|title=An Introduction to Abstract Harmonic Analysis| publisher=van Nostrand|year=1953}}, [http://www.archive.org/details/introductiontoab031610mbp page 40].</ref> | |||
:<math> |\mu|(f) = \sup_{0\le |g|\le f} |\mu(g)|.</math> | |||
The form |μ| extends linearly to a bounded linear form on C[''a'', ''b''] with norm ||μ|| and satisfies the characterizing inequality | |||
:|μ(''f'')| ≤ |μ|(|''f''|) | |||
for ''f'' in C[''a'', ''b'']. If μ is ''real'', i.e. is real-valued on real-valued functions, then | |||
:<math> \mu = |\mu| -(|\mu| -\mu)\equiv \mu_+-\mu_-</math> | |||
gives a canonical decomposition as a difference of ''positive'' forms, i.e. forms that are non-negative on non-negative functions. | |||
Every positive form μ extends uniquely to the linear span of non-negative bounded lower [[semicontinuous function]]s ''g'' by the formula<ref>{{harvnb|Loomis|1953|pp=30–31}}</ref> | |||
:<math> \mu(g) = \lim \mu(f_n),</math> | |||
where the non-negative continuous functions ''f''<sub>''n''</sub> increase pointwise to ''g''. | |||
The same therefore applies to an arbitrary bounded linear form μ, so that a function ρ of bounded variation may be defined by<ref>{{citation|first=A.N.|last=Kolmogorov|first2=S.V.|last2=Fomin|title=Introductory Real Analysis|isbn=0-486-61226-0|publisher=Dover|year=1975|pages= 374–376}}</ref> | |||
:<math>\rho(x)=\mu(\chi_{[a,x]}),</math> | |||
where χ<sub>''A''</sub> denotes the [[Indicator function|characteristic function]] of a subset ''A'' of [''a'', ''b'']. Thus μ = ''d''ρ and ||μ|| = ||''d''ρ||. | |||
Moreover μ<sub>+</sub> = ''d''ρ<sub>+</sub> and μ<sub>–</sub> = ''d''ρ<sub>–</sub>. | |||
This correspondence between functions of bounded variation and bounded linear forms is a special case of the '''[[Riesz representation theorem]]'''. | |||
The [[support (measure theory)|support]] of μ = ''d''ρ is the complement of all points ''x'' in [''a'',''b''] where ρ is constant on some neighborhood of ''x''; by definition it is a closed subset ''A'' of [''a'',''b'']. Moreover μ((1-χ<sub>''A''</sub>)''f'') =0, so that μ(''f'') = 0 if ''f'' vanishes on ''A''. | |||
===Spectral measure=== | |||
{{See also|Spectral theorem|Projection-valued measure}} | |||
Let ''H'' be a Hilbert space and ''T'' a self-adjoint [[bounded operator]] on ''H'' with 0 ≤ ''T'' ≤ I, so that the [[spectrum (functional analysis)|spectrum]] σ(''T'') of ''T'' is contained in [0,1]. If ''p''(''t'') is a complex polynomial, then by the ''spectral mapping theorem'' | |||
:σ(''p''(''T'')) = ''p''(σ(''T'')) | |||
and hence | |||
:||''p''(''T'')|| ≤ ||''p''||<sub>∞</sub>, | |||
where ||·||<sub>∞</sub> denotes the [[uniform norm]] on C[0,1]. By the [[Weierstrass approximation theorem]], polynomials are uniformly dense in C[0, 1]. It follows that ''f''(''T'') can be defined for every ''f'' in C[0,1], with | |||
:σ(''f''(''T'')) = ''f''(σ(''T'')) and ||''f''(''T'')|| ≤ ||''f''||<sub>∞</sub>. | |||
If 0 ≤ ''g'' ≤ 1 is a lower semicontinuous function on [0,1], for example the characteristic function χ<sub>[0,α]</sub> of a subinterval of [0,1], then | |||
''g'' is a pointwise increasing limit of non-negative ''f''<sub>''n''</sub> in C[0,1]. | |||
According to [[Béla Szőkefalvi-Nagy|Sz.-Nagy]],<ref>{{harvnb|Riesz|Nagy|1990|p=263}}</ref> if ξ is a vector in ''H'', then the vectors | |||
:η<sub>''n''</sub> = ''f''<sub>''n''</sub>(''T'') ξ | |||
form a [[Cauchy sequence]] in ''H'', since, for ''n'' ≥ ''m'', | |||
:<math> \|\eta_n-\eta_m\|^2 \le (\eta_n,\xi) - (\eta_m,\xi),</math> | |||
and (η<sub>''n''</sub>,ξ) = (''f''<sub>''n''</sub>(T)ξ, ξ) is bounded and increasing, so has a limit. | |||
It follows that ''g''(''T'') can be defined by<ref>This is a limit in the [[strong operator topology]].</ref> | |||
:''g''(''T'')ξ = lim ''f''<sub>''n''</sub>(''T'')ξ. | |||
If ξ and η are vectors in ''H'', then | |||
:<math>\mu_{\xi,\eta}(f) = (f(T) \xi,\eta)</math> | |||
defines a bounded linear form μ<sub>ξ,η</sub> on ''H''. By the Riesz representation theorem | |||
:<math>\mu_{\xi,\eta}=d\rho_{\xi,\eta}</math> | |||
for a unique normalised function ρ<sub>ξ,η</sub> of bounded variation on [0,1]. | |||
dρ<sub>ξ,η</sub> (or sometimes slightly incorrectly ρ<sub>ξ,η</sub> itself) is called the '''spectral measure''' | |||
determined by ξ and η. | |||
The operator ''g''(''T'') is accordingly uniquely characterised by the equation | |||
:<math> (g(T)\xi,\eta) = \mu_{\xi,\eta}(g) = \int_0^1 g(\lambda) \, d\rho_{\xi,\eta}(\lambda).</math> | |||
The [[spectral theorem|spectral projection]] ''E''(λ) is defined by | |||
:<math>E(\lambda)=\chi_{[0,\lambda]}(T),</math> | |||
so that | |||
:<math>\rho_{\xi,\eta}(\lambda)=(E(\lambda)\xi,\eta).</math> | |||
It follows that | |||
:<math> g(T) = \int_0^1 g(\lambda) \,dE(\lambda),</math> | |||
which is understood in the sense that for any vectors ξ and η, | |||
: <math> (g(T)\xi,\eta) = \int_0^1 g(\lambda)\, d(E(\lambda)\xi,\eta) = \int_0^1 g(\lambda)\, d\rho_{\xi,\eta}(\lambda). </math> | |||
For a single vector ξ, μ<sub>ξ</sub> = μ<sub>ξ,ξ</sub> is a positive form on [0,1] | |||
(in other words proportional to a [[probability measure]] on [0,1]) and ρ<sub>ξ</sub> = ρ<sub>ξ,ξ</sub> is non-negative and non-decreasing. | |||
Polarisation shows that all the forms μ<sub>ξ,η</sub> can naturally be expressed in terms of such positive forms, since | |||
:μ<sub>ξ,η</sub> = ¼(μ<sub>ξ+η</sub> + i μ<sub>ξ+iη</sub> − μ<sub>ξ−η</sub> −i μ<sub>ξ−iη</sub>). | |||
If the vector ξ is such that the [[linear span]] of the vectors (''T''<sup>''n''</sup>ξ) is dense in ''H'', i.e. ξ is a ''cyclic vector'' for | |||
''T'', then the map ''U'' defined by | |||
:<math> U(f) = f(T)\xi, \, C[0,1] \rightarrow H</math> | |||
satisfies | |||
:<math> (Uf_1,Uf_2)= \int_0^1 f_1(\lambda) \overline{f_2(\lambda)} \, d\rho_\xi(\lambda).</math> | |||
Let L<sup>2</sup>([0,1], ''d''ρ<sub>ξ</sub>) denote the Hilbert space completion of C[0,1] associated | |||
with the possibly [[inner product#Degenerate inner products|degenerate inner product]] on the right hand side.<ref>A ''bona fide'' inner product is defined on the quotient by the subspace of null functions ''f'', i.e. those with μ<sub>ξ</sub>(|''f''|<sup>2</sup>)=0. Alternatively in this case the support of the measure is σ(''T''), so the right hand side defines a (non-degenerate) inner product on C(σ(''T'')).</ref> | |||
Thus ''U'' extends to a [[unitary transformation]] of L<sup>2</sup>([0,1], ''d''ρ<sub>ξ</sub>) onto ''H''. ''UTU''* is then just multiplication by λ on L<sup>2</sup>([0,1], ''d''ρ<sub>ξ</sub>); and more generally ''Uf(T)U''* is multiplication by ''f''(λ). In this case, the support of ''d''ρ<sub>ξ</sub> | |||
is exactly σ(''T''), so that | |||
* ''the self-adjoint operator becomes a multiplication operator on the space of functions on its spectrum with inner product given by the spectral measure''. | |||
== Weyl–Titchmarsh–Kodaira theory == | |||
The eigenfunction expansion associated with singular differential operators of the form | |||
:<math> Df = -(pf^\prime)^\prime + qf</math> | |||
on an open interval (''a'', ''b'') requires an initial analysis of the behaviour of the fundamental | |||
eigenfunctions near the endpoints ''a'' and ''b'' to determine possible [[boundary condition]]s there. Unlike the regular Sturm–Liouville case, in some circumstances [[spectral theory|spectral values]] of ''D'' can have [[Multiplicity (mathematics)|multiplicity]] 2. In the development outlined below standard assumptions will be imposed on ''p'' and ''q'' that guarantee that the spectrum of | |||
''D'' has multiplicity one everywhere and is bounded below. This includes almost all important applications; modifications required for the more general case will be discussed later. | |||
Having chosen the boundary conditions, as in the classical theory the resolvent of ''D'', (''D'' + ''R'' )<sup>−1</sup> for ''R '' large and positive, is given by an operator ''T'' corresponding to a Green's function constructed from two fundamental eigenfunctions. In the classical case ''T'' was a compact self-adjoint operator; in this case ''T'' is just a self-adjoint bounded operator with 0 ≤ ''T'' ≤ I. The abstract theory of spectral measure can therefore be applied to ''T'' to give the eigenfunction expansion for ''D''. | |||
The central idea in the proof of Weyl and Kodaira can be explained informally as follows. Assume that the spectrum of ''D'' lies in [1,∞) and that ''T'' =''D''<sup>−1</sup> and let | |||
:<math> E(\lambda) =\chi_{[\lambda^{-1},1]}(T)</math> | |||
be the spectral projection of ''D'' corresponding to the interval [1,λ]. For an arbitrary function ''f'' define | |||
:<math> f(x,\lambda)= (E(\lambda)f)(x). </math> | |||
''f''(''x'',λ) may be regarded as a differentiable map into the space of functions of bounded variation ρ; or equivalently as a differentiable map | |||
:<math> x\mapsto (d_\lambda f)(x)</math> | |||
into the Banach space '''E''' of bounded linear functionals ''d''ρ on C[α,β] whenever [α,β] is a compact subinterval of [1, ∞). | |||
Weyl's fundamental observation was that ''d''<sub>λ</sub> ''f'' satisfies a second order ordinary differential equation taking values in '''E''': | |||
:<math> D (d_\lambda f) = \lambda \cdot d_\lambda f.</math> | |||
After imposing initial conditions on the first two derivatives at a fixed point ''c'', this equation can be solved explicitly | |||
in terms of the two fundamental eigenfunctions and the "initial value" functionals | |||
:<math> (d_\lambda f)(c)= d_\lambda f(c,\cdot), \quad (d_\lambda f)^\prime(c)= d_\lambda f_x(c,\cdot).</math> | |||
This point of view may now be turned on its head: ''f''(''c'',λ) and ''f''<sub>''x''</sub>(''c'',λ) may be written as | |||
:<math> f(c,\lambda)=(f,\xi_1(\lambda)), \quad f_x(c,\lambda)=(f,\xi_2(\lambda)),</math> | |||
where ξ<sub>1</sub>(λ) and ξ<sub>2</sub>(λ) are given purely in terms of the fundamental eigenfunctions. | |||
The functions of bounded variation | |||
:<math> \sigma_{ij}(\lambda) = (\xi_i(\lambda),\xi_j(\lambda))</math> | |||
determine a spectral measure on the spectrum of ''D'' and can be computed explicitly from the behaviour | |||
of the fundamental eigenfunctions (the Titchmarsh–Kodaira formula). | |||
=== Limit circle and limit point for singular equations === | |||
Let ''q''(''x'') be a continuous real-valued function on (0,∞) | |||
and let ''D'' be the second order differential operator | |||
:<math> Df= -f^{\prime\prime} + qf</math> | |||
on (0,∞). Fix a point ''c'' in (0,∞) and, for λ complex, let <math>\varphi_\lambda, \theta_\lambda</math> be the unique '''fundamental eigenfunctions''' of ''D'' on (0,∞) satisfying | |||
:<math> (D-\lambda)\varphi_\lambda = 0, \quad (D-\lambda)\theta_\lambda =0 </math> | |||
together with the initial conditions at ''c'' | |||
:<math> \varphi_\lambda(c)=1,\, \varphi_\lambda^\prime(c)=0, \, \theta_\lambda(c)=0, \, \theta_\lambda^\prime(c)=1.</math> | |||
Then their Wronskian satisfies | |||
:<math> W(\varphi_\lambda,\theta_\lambda) = \varphi_\lambda\theta_\lambda^\prime- \theta_\lambda \varphi_\lambda^\prime\equiv 1,</math> | |||
since it is constant and equal to 1 at ''c''. | |||
If λ is non-real and 0 < ''x'' < ∞, then Green's formula implies | |||
:<math> 2 \, {\rm Im}(\lambda) \int_c^x |\varphi +\mu \theta|^2 =-{\rm Im}(\mu).</math> | |||
This defines a [[circle]] in the complex μ-plane, the [[interior (topology)|interior]] of which is given by | |||
:<math> \int_c^x | \varphi +\mu \theta|^2 <-{{\rm Im}(\mu)\over 2\, {\rm Im}(\lambda)}</math> | |||
if ''x'' > ''c'' and by | |||
:<math> \int_x^c | \varphi +\mu \theta|^2 <-{{\rm Im}(\mu)\over 2\, {\rm Im}(\lambda)}</math> | |||
if ''x'' < ''c''. | |||
Let ''D''<sub>''x''</sub> be the closed disc enclosed by the circle. By definition | |||
these closed discs are nested and decrease as ''x'' approaches 0 or ∞. So in the limit, the circles | |||
tend either to a '''limit circle''' or a '''limit point''' at each end. In particular if μ is a | |||
limit point or a point on the limit circle at 0 or ∞, then <math>|\varphi + \mu\theta|^2</math> is | |||
[[square integrable]] (L<sup>2</sup>) near 0 or ∞. In particular:<ref name="Weyl 1910">{{harvnb|Weyl|1910}}</ref> | |||
* ''there are always non-zero solutions of Df = λf which are square integrable near 0 or ∞''; | |||
* ''there is exactly one non-zero solution (up to scalar multiples) of Df = λf which is square integrable near 0 or ∞ precisely in the limit point case''. | |||
On the other hand if ''Dg'' = λ' ''g'' for another value λ', then | |||
:<math> h(x) = g(x) -(\lambda^\prime-\lambda) \int_c^x (\varphi_\lambda(x) \theta_\lambda(y) - \theta_\lambda(x)\varphi_\lambda(y))g(y)\, dy</math> | |||
satisfies ''Dh'' = λ''h'', so that | |||
:<math>g(x)=c_1 \varphi_\lambda + c_2 \theta_\lambda + (\lambda^\prime-\lambda) \int_c^x (\varphi_\lambda(x) \theta_\lambda(y) - \theta_\lambda(x)\varphi_\lambda(y))g(y)\, dy.</math> | |||
Using this to estimate ''g'', it follows that<ref name="Weyl 1910"/> | |||
* ''the limit point/limit circle behaviour at 0 or ∞ is independent of the choice of λ''. | |||
More generally if ''Dg''= (λ – ''r'') ''g'' for some function ''r''(''x''), then<ref name="Bellman 1969 116">{{harvnb|Bellman|1969|p=116}}</ref> | |||
:<math>g(x)=c_1 \varphi_\lambda + c_2 \theta_\lambda - \int_c^x (\varphi_\lambda(x) \theta_\lambda(y) - \theta_\lambda(x)\varphi_\lambda(y))r(y)g(y)\, dy.</math> | |||
From this it follows that<ref name="Bellman 1969 116"/> | |||
* ''if r is continuous at 0, then D + r is limit point or limit circle at 0 precisely when D is'', | |||
so that in particular<ref>{{harvnb|Reed|Simon|1975|p=159}}</ref> | |||
* ''if q(x)- a/x<sup>2</sup> is continuous at 0, then D is limit point at 0 if and only if a ≥ ¾''. | |||
Similarly | |||
* ''if r has a finite limit at ∞, then D + r is limit point or limit circle at ∞ precisely when D is'', | |||
so that in particular<ref>{{harvnb|Reed|Simon|1975|p=154}}</ref> | |||
* ''if q has a finite limit at ∞, then D is limit point at ∞''. | |||
Many more elaborate criteria to be limit point or limit circle can be found in the mathematical literature. | |||
=== Green's function (singular case) === | |||
Consider the differential operator | |||
:<math> D_0 f = -(p_0f^\prime)^\prime + q_0f</math> | |||
on (0,∞) with ''q''<sub>0</sub> positive and continuous on (0,∞) and ''p''<sub>0</sub> continuously differentiable in [0,∞), positive in (0,∞) and ''p''<sub>0</sub>(0)=0. | |||
Moreover assume that after reduction to standard form | |||
''D''<sub>0</sub> becomes the equivalent operator | |||
:<math> Df= -f^{\prime\prime} + qf</math> | |||
on (0,∞) where ''q'' has a finite limit at ∞. Thus | |||
*''D is limit point at ∞''. | |||
At 0, ''D'' may be either limit circle or limit point. In either case there is an eigenfunction Φ<sub>0</sub> with ''D''Φ<sub>0</sub>=0 and Φ<sub>0</sub> square integrable near 0. In the limit circle case, Φ<sub>0</sub> determines a '''[[boundary condition]]''' at 0: | |||
:<math> W(f,\Phi_0)(0)=0.</math> | |||
For λ complex, let Φ<sub>λ</sub> and Χ<sub>λ</sub> satisfy | |||
* (''D'' – λ)Φ<sub>λ</sub> = 0, (''D'' – λ)Χ<sub>λ</sub> = 0 | |||
* Χ<sub>λ</sub> square integrable near infinity | |||
* Φ<sub>λ</sub> square integrable at 0 if 0 is ''limit point'' | |||
* Φ<sub>λ</sub> satisfies the boundary condition above if 0 is ''limit circle''. | |||
Let | |||
:<math>\omega(\lambda) = W(\Phi_\lambda,\Chi_\lambda),</math> | |||
a constant which vanishes precisely when Φ<sub>λ</sub> and Χ<sub>λ</sub> are proportional, i.e. λ is an [[eigenvalue]] of ''D'' for these boundary conditions. | |||
On the other hand, this cannot occur if Im λ ≠ 0 or if λ is negative.<ref name="Weyl 1910"/> | |||
Indeed if ''D f''= λ''f'' with ''q''<sub>0</sub> – λ ≥ δ >0, then by Green's formula (''Df'',''f'') = (''f'',''Df''), since ''W''(''f'',''f''<sup>*</sup>) is constant. So λ must be real. If ''f'' is taken to be real-valued in the ''D''<sub>0</sub> realization, then for 0 < ''x'' < ''y'' | |||
:<math> [p_0 ff^\prime]_x^y = \int_x^y (q_0 -\lambda)|f|^2 + p_0 (f^\prime)^2 .</math> | |||
Since ''p''<sub>0</sub>(0) = 0 and ''f'' is integrable near 0, ''p''<sub>0</sub>''f'' ''f'' ' must vanish at 0. Setting ''x'' = 0, it follows that ''f''(''y'') ''f'' '(''y'') >0, so that ''f''<sup>2</sup> is increasing, contradicting the square integrability of ''f'' near ∞. | |||
Thus, adding a positive scalar to ''q'', it may be assumed that | |||
:''ω(λ) ≠ 0 when λ is not in [1,∞)''. | |||
If ω(λ) ≠ 0, the '''[[Green's function]]''' ''G''<sub>λ</sub>(''x'',''y'') at λ is defined by | |||
:<math>G_\lambda(x,y) = \Phi_\lambda(x)\Chi_\lambda(y)/\omega(\lambda) \,\, (x\le y), \,\,\,\, | |||
\Chi_\lambda(x)\Phi_\lambda(y)/\omega(\lambda) \,\, (x\ge y).</math> | |||
and is independent of the choice of <sub>λ</sub> and Χ<sub>λ</sub>. | |||
In the examples there will be a third "bad" eigenfunction Ψ<sub>λ</sub> defined and holomorphic for λ not in [1, ∞) such that | |||
Ψ<sub>λ</sub> satisfies the boundary conditions at neither 0 nor ∞. This means that for λ not in [1, ∞) | |||
* ''W''(Φ<sub>λ</sub>,Ψ<sub>λ</sub>) is nowhere vanishing; | |||
* ''W''(Χ<sub>λ</sub>,Ψ<sub>λ</sub>) is nowhere vanishing. | |||
In this case Χ<sub>λ</sub> is proportional to Φ<sub>λ</sub> + ''m''(λ) Ψ<sub>λ</sub>, where | |||
* ''m''(λ) = – ''W''(Φ<sub>λ</sub>,Χ<sub>λ</sub>) / ''W''(Ψ<sub>λ</sub>,Χ<sub>λ</sub>). | |||
Let ''H''<sub>1</sub> be the space of square integrable continuous functions on (0,∞) and let ''H''<sub>0</sub> be | |||
* the space of C<sup>2</sup> functions ''f'' on (0,∞) of [[compact support]] if ''D'' is limit point at 0 | |||
* the space of C<sup>2</sup> functions ''f'' on (0,∞) with ''W''(''f'',Φ<sub>0</sub>)=0 at 0 and with ''f'' = 0 near ∞ if ''D'' is limit circle at 0. | |||
Define ''T'' = ''G''<sub>0</sub> by | |||
:<math>(Tf)(x) =\int_0^\infty G_0(x,y)f(y) \, dy. </math> | |||
Then ''T'' ''D'' = ''I'' on ''H''<sub>0</sub>, ''D'' ''T'' = ''I'' on ''H''<sub>1</sub> and the operator ''D'' is bounded below on ''H''<sub>0</sub>: | |||
:<math>(Df,f) \ge (f,f).</math> | |||
Thus ''T'' is a self-adjoint bounded operator with 0 ≤ ''T'' ≤ ''I''. | |||
Formally ''T'' = ''D''<sup>−1</sup>. The corresponding operators ''G''<sub>λ</sub> defined for λ not in [1,∞) can be formally identified with | |||
:<math>(D-\lambda)^{-1}=T(I-\lambda T)^{-1}</math> | |||
and satisfy ''G''<sub>λ</sub> (''D'' – λ) = ''I'' on ''H''<sub>0</sub>, (''D'' – λ)''G''<sub>λ</sub> = ''I'' on ''H''<sub>1</sub>. | |||
=== Spectral theorem and Titchmarsh–Kodaira formula === | |||
'''Theorem'''.<ref name="Weyl 1910"/><ref>{{harvnb|Titchmarsh |1946}}, Chapter III.</ref><ref>{{harvnb|Kodaira|1949|pp=935–936}}</ref> ''For every real number λ let ρ(λ) be defined by the'' '''Titchmarsh–Kodaira formula''': | |||
:<math> \rho(\lambda) = \lim_{\delta \downarrow 0} \lim_{\varepsilon \downarrow 0} {1\over \pi} \int_\delta^{\lambda+\delta} {\rm Im}\, m(t + i\varepsilon) \, dt.</math> | |||
''Then ρ(λ) is a lower semicontinuous non-decreasing function of λ and if'' | |||
:<math> (Uf)(\lambda) = \int_0^\infty f(x) \Phi(x,\lambda) \, dx,</math> | |||
''then U defines a unitary transformation of L<sup>2</sup>(0,∞) onto L<sup>2</sup>([1,∞), dρ) such that'' | |||
UDU<sup>−1</sup> ''corresponds to multiplication by λ. '' | |||
''The inverse transformation U<sup>−1</sup> is given by'' | |||
:<math> (U^{-1}g)(x) = \int_1^\infty g(\lambda) \Phi(x,\lambda) \, d\rho(\lambda).</math> | |||
''The spectrum of D equals the support of dρ.'' | |||
Kodaira gave a streamlined version<ref>{{harvnb|Kodaira|1949|pp=929–932}}; for omitted details, see {{harvnb|Kodaira|1950|pp=529–536}}</ref><ref>{{harvnb|Dieudonné|1988}}</ref> of Weyl's original proof.<ref name="Weyl 1910"/> ([[Marshall Harvey Stone|M.H. Stone]] had previously shown<ref>{{harvnb|Stone|1932}}, Chapter X.</ref> how part of Weyl's work could be simplified using von Neumann's spectral theorem.) | |||
In fact for ''T'' =''D''<sup>−1</sup> with 0 ≤ ''T'' ≤ ''I'', the spectral projection ''E''(λ) of ''T'' is defined by | |||
:<math> E(\lambda) =\chi_{[\lambda^{-1},1]}(T)</math> | |||
It is also the spectral projection of ''D'' corresponding to the interval [1,λ]. | |||
For ''f'' in ''H''<sub>1</sub> define | |||
:<math> f(x,\lambda)= (E(\lambda)f)(x). </math> | |||
''f''(''x'',λ) may be regarded as a differentiable map into the space of functions ρ of bounded variation; or equivalently as a differentiable map | |||
:<math> x\mapsto (d_\lambda f)(x)</math> | |||
into the Banach space '''E''' of bounded linear functionals ''d''ρ on C[α,β] for any compact subinterval [α,β] of [1, ∞). | |||
The functionals (or measures) ''d''<sub>λ</sub> ''f''(''x'') satisfies the following '''E'''-valued second order ordinary differential equation: | |||
:<math> D (d_\lambda f) = \lambda \cdot d_\lambda f,</math> | |||
with initial conditions at ''c'' in (0,∞) | |||
<math> (d_\lambda f)(c)= d_\lambda f(c,\cdot)=\mu^{(0)}, \quad (d_\lambda f)^\prime(c)= d_\lambda f_x(c,\cdot)=\mu^{(1)}.</math> | |||
If φ<sub>λ</sub> and χ<sub>λ</sub> are the special eigenfunctions adapted to ''c'', then | |||
:<math> d_\lambda f (x) = \varphi_\lambda(x) \mu^{(0)} + \chi_\lambda(x) \mu^{(1)}.</math> | |||
Moreover | |||
:<math> \mu^{(k)}= d_\lambda (f,\xi^{(k)}_\lambda),</math> | |||
where | |||
:<math> \xi^{(k)}_\lambda = D E(\lambda) \eta^{(k)},</math> | |||
with | |||
:<math> \eta_z^{(0)}(y) = G_z(c,y), \,\,\,\, \eta_z^{(1)}(x)=\partial_x G_z(c,y), \,\,\,\, (z \notin [1,\infty)).</math> | |||
(As the notation suggests, ξ<sub>λ</sub><sup>(0)</sup> and ξ<sub>λ</sub><sup>(1)</sup> do not depend on the choice of ''z''.) | |||
Setting | |||
:<math>\sigma_{ij}(\lambda) = (\xi^{(i)}_\lambda, \xi^{(j)}_\lambda),</math> | |||
it follows that | |||
:<math> d_\lambda (E(\lambda)\eta_z^{(i)},\eta_z^{(j)}) = |\lambda - z|^{-2} \cdot d_\lambda \sigma_{ij}(\lambda).</math> | |||
On the other hand there are holomorphic functions | |||
''a''(λ), ''b''(λ) such that | |||
* φ<sub>λ</sub> + ''a''(λ) χ<sub>λ</sub> is proportional to Φ<sub>λ</sub>; | |||
* φ<sub>λ</sub> + ''b''(λ) χ<sub>λ</sub> is proportional to Χ<sub>λ</sub>. | |||
Since ''W''(φ<sub>λ</sub>,χ<sub>λ</sub>) = 1, the Green's function is given by | |||
:<math> G_\lambda(x,y) = {(\varphi_\lambda(x) + a(\lambda)\chi_\lambda(x))(\varphi_\lambda(y) + b(\lambda)\chi_\lambda(y))\over b(\lambda)-a(\lambda)} \,\, (x\le y), \,\,\,\, {(\varphi_\lambda(x) + b(\lambda)\chi_\lambda(x))(\varphi_\lambda(y) + a(\lambda)\chi_\lambda(y))\over b(\lambda)-a(\lambda)} \,\, (y\le x). </math> | |||
Direct calculation<ref>{{harvnb|Kodaira|1950|pp=534–535}}</ref> shows that | |||
:<math>(\eta_z^{(i)},\eta_z^{(j)}) = {\rm Im}\, M_{ij}(z)/ {\rm Im}\, z, </math> | |||
where the so-called ''' ''characteristic matrix'' ''' ''M''<sub>''ij''</sub>(''z'') is given by | |||
:<math> M_{00}(z)= {a(z)b(z)\over a(z)-b(z)},\,\, M_{01}(z)=M_{10}(z)={a(z)+b(z)\over 2(a(z) -b(z))}, \,\, M_{11}(z)= {1\over a(z)-b(z)}.</math> | |||
Hence | |||
:<math> \int_{-\infty}^\infty ({\rm Im}\, z)\cdot|\lambda-z|^{-2}\, d\sigma_{ij}(\lambda) = {\rm Im} M_{ij}(z),</math> | |||
which immediately implies | |||
:<math> \sigma_{ij}(\lambda) = \lim_{\delta\downarrow 0} \lim_{\varepsilon \downarrow 0} \int_\delta^{\lambda +\delta}{\rm Im}\, M_{ij}(t +i\varepsilon)\, dt.</math> | |||
(This is a special case of the [[Stieltjes transformation|"Stietljes inversion formula"]].) | |||
Setting ψ<sub>λ</sub><sup>(0)</sup>=φ<sub>λ</sub> and ψ<sub>λ</sub><sup>(1)</sup>=χ<sub>λ</sub>, it follows that | |||
:<math> (E(\mu)f)(x)= \sum_{i.j}\int_0^\mu \int_0^\infty\psi^{(i)}_\lambda(x)\psi^{(j)}_\lambda(y) f(y)\, dy \,d\sigma_{ij}(\lambda) = \int_0^\mu \int_0^\infty\Phi_\lambda(x) \Phi_\lambda(y) f(y)\, dy \, d\rho(\lambda).</math> | |||
This identity is equivalent to the spectral theorem and Titchmarsh–Kodaira formula. | |||
== Application to the hypergeometric equation == | |||
{{See also|Legendre equation|Hypergeometric equation}} | |||
The '''Mehler–Fock transform'''<ref>{{citation|last=Mehler|first=F.G.|title=Ueber mit der Kugel- und Cylinderfunctionen verwandte Function und ihre Anwendung in der Theorie der Elektricitätsverteilung|journal=[[Mathematische Annalen]]|year=1881|volume=18|pages=161–194|doi=10.1007/BF01445847|url=http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=PPN235181684_0018&DMDID=DMDLOG_0021&L=1}}</ref><ref>{{citation|last=Fock|first=V.A.|title=On the representation of an arbitrary function by an integral involving Legendre's functions with a complex index|journal=C. R. (Doklady) Acad. Sci. URSS |year=1943|volume=39|pages=253–256}}</ref><ref>{{harvnb|Vilenkin|1968}}</ref> concerns the eigenfunction expansion associated with the [[Legendre function|Legendre differential operator]] ''D'' | |||
:<math> Df = -((x^2-1) f^\prime)^\prime =-(x^2-1)f^{\prime\prime} -2x f^\prime </math> | |||
on (1,∞). The eigenfunctions are the [[Legendre function]]s<ref>{{citation|first=Audrey|last=Terras|authorlink=Audrey Terras|title=Non-Euclidean harmonic analysis, the central limit theorem, and long transmission lines with random inhomogeneities|journal=J. Multivariate Anal.|volume= 15 |year=1984|pages=261–276|doi=10.1016/0047-259X(84)90031-9}}</ref> | |||
:<math> P_{-1/2+i\sqrt{\lambda}}(\cosh r) = {1\over 2\pi} \int_0^{2\pi} \left({\sin \theta + i e^{-r} \cos\theta\over \cos \theta - i e^{-r}\sin\theta} \right)^{{1\over 2}+i\sqrt{\lambda}}\, d\theta</math> | |||
with eigenvalue λ ≥ 0. The two Mehler–Fock transformations are<ref>{{citation|first=N.N.|last=Lebedev|title=Special Functions and Their Applications|year=1972| | |||
publisher=Dover|isbn=0-486-60624-4}}</ref> | |||
:<math>Uf(\lambda)=\int_1^\infty f(x)\, P_{-1/2 +i\sqrt{\lambda}}(x) \, dx</math> | |||
and | |||
:<math>U^{-1}g(x)=\int_0^\infty g(\lambda) \, {1\over2}\tanh \pi \sqrt{\lambda}\,d\lambda.</math> | |||
(Often this is written in terms of the variable τ = √λ.) | |||
Mehler and Fock studied this differential operator because it arose as the radial component of the Laplacian on 2-dimensional hyperbolic space. | |||
More generally,<ref>{{harvnb|Vilenkin|1968}}, Chapter VI.</ref> consider the group ''G'' = [[SL(2,R)|SU(1,1)]] consisting of complex matrices of the form | |||
:<math> \left(\begin{matrix}\alpha & \beta\\ | |||
\overline{\beta} & \overline{\alpha}\end{matrix}\right)</math> | |||
with determinant |α|<sup>2</sup> − |β|<sup>2</sup> = 1. | |||
== Application to the hydrogen atom == | |||
{{See also|Hydrogen atom}} | |||
== Generalisations and alternative approaches == | |||
A Weyl function can be defined at a singular endpoint <math>a</math> giving rise to a singular version of Weyl–Titchmarsh–Kodaira theory.<ref>{{citation|first=Aleksey|last=Kostenko|first2=Alexander|last2=Sakhnovich|first3=Gerald|last3=Teschl|authorlink3=Gerald Teschl|title=Weyl–Titchmarsh Theory for Schrödinger Operators with Strongly Singular Potentials|journal=Int Math Res Notices|volume= 2012 |year=2012|pages=1699-1747|doi=10.1093/imrn/rnr065|arxiv=1007.0136}}</ref> this applies for example to the case of radial Schrödinger operators | |||
:<math> Df = -f^{\prime\prime} + \frac{l(l+1)}{x^2} f+ V(x) f, \qquad x\in(0,\infty) </math> | |||
The whole theory can also be extended to the case where the coefficients are allowed to be measures.<ref>{{citation|first=Jonathan|last=Eckhardt|first2=Gerald|last2=Teschl|authorlink2=Gerald Teschl|title=Sturm–Liouville operators with measure-valued coefficients|journal=J. d'Analyse Math.|volume=120|year=2013|pages=151-224|doi=10.1007/s11854-013-0018-x|arxiv=1105.3755}}</ref> | |||
== Gelfand–Levitan theory == | |||
{{See also|Inverse scattering theory}} | |||
==Notes== | |||
{{reflist|2}} | |||
==References== | |||
*{{citation|first=Naum Ilich|last=[[Naum Akhiezer|Akhiezer]]|first2=Izrael Markovich|last2=Glazman|title=Theory of Linear Operators in Hilbert Space|publisher=Dover|year=1993|isbn=0-486-67748-6}} | |||
*{{citation|first=Richard|last= Bellman|title=Stability Theory of Differential Equations|publisher=Dover|year=1969|isbn=0-486-62210-X}} | |||
*{{citation|first=Earl A.|last= Coddington|first2=Norman|last2=Levinson|year= 1955|publisher= McGraw-Hill|title=Theory of Ordinary Differential equations|isbn=0-07-011542-7}} | |||
*{{citation|last=[[Richard Courant|Courant]]|first=Richard|first2=David|last2=Hilbert|title=Method of Mathematical Physics, Vol. I|publisher=Wiley-Interscience|year=1989|isbn=0-471-50447-5}} | |||
*{{citation|first=Jean|last=[[Jean Dieudonné|Dieudonné]]|title=Treatise on Analysis, Vol. I [Foundations of Modern Analysis]|publisher=Academic Press|year=1969| | |||
isbn=1-4067-2791-1}} | |||
*{{citation|first=Jean|last=Dieudonné|title=Treatise on Analysis, Vol. VIII|publisher=Academic Press|year=1988|isbn= 0-12-215507-6}} | |||
*{{citation|first=Nelson|last=[[Nelson Dunford|Dunford]]|first2=Jacob T.| last2=Schwartz|title=Linear Operators, Part II Spectral Theory. Self Adjoint Operators in Hilbert space|year=1963|publisher=Wiley Interscience|isbn=0-471-60847-5}} | |||
*{{citation|first=Einar|last=[[Einar Hille|Hille]]|title=Lectures on Ordinary Differential Equations|year=1969|publisher=Addison-Wesley|isbn= 0-201-53083-X}} | |||
*{{citation|first=Kunihiko|last=[[Kunihiko Kodaira|Kodaira]]|title= The eigenvalue problem for ordinary differential equations of the second order and Heisenberg's theory of S-matrices|journal=American Journal of Mathematics|year=1949|volume=71|pages=921–945|doi=10.2307/2372377|url=http://jstor.org/stable/2372377|issue=4|publisher=The Johns Hopkins University Press}} | |||
*{{citation|first=Kunihiko|last=Kodaira|title=On ordinary differential equations of any even order and the corresponding eigenfunction expansions|journal= American Journal of Mathematics|year=1950|volume=72|pages=502–544|doi=10.2307/2372051|url=http://jstor.org/stable/2372051|issue=3|publisher=The Johns Hopkins University Press}} | |||
*{{citation|first=Michael|last=[[Michael C. Reed|Reed]]|first2=Barry|last2=[[Barry Simon|Simon]]|title=Methods of Modern Mathematical Physics II, Fourier Analysis, Self-Adjointness|publisher=Academic Press|year=1975|isbn= 0-12-585002-6}} | |||
*{{citation|first=Marshall Harvey|last=[[Marshall Harvey Stone|Stone]]|title=Linear transformations in Hilbert space and Their Applications to Analysis|series=AMS Colloquium Publications|volume=16|year=1932|isbn=0-8218-1015-4}} | |||
*{{cite book| last = Teschl| given = Gerald|authorlink=Gerald Teschl| title=Mathematical Methods in Quantum Mechanics; With Applications to Schrödinger Operators|url=http://www.mat.univie.ac.at/~gerald/ftp/book-schroe/|series=AMS Graduate Studies in Mathematics|volume=99|year=2009|isbn=0-8218-4660-4}} | |||
*{{cite book| last = Teschl| given = Gerald|authorlink=Gerald Teschl| title = Ordinary Differential Equations and Dynamical Systems| series=AMS Graduate Studies in Mathematics|volume=140| year = 2012| isbn= 978-0-8218-8328-0| url = http://www.mat.univie.ac.at/~gerald/ftp/book-ode/}} | |||
*{{citation|first=Edward Charles|last=[[Edward Charles Titchmarsh|Titchmarsh]]| title=Eigenfunction expansions associated with second order differential equations, Vol. I, first edition|year=1946|publisher=Oxford University Press}} | |||
*{{citation|first=Edward Charles|last=Titchmarsh| title=Eigenfunction expansions associated with second order differential equations, Vol. I, second edition|year=1962|publisher=Oxford University Press|isbn=0-608-08254-6}} | |||
*{{citation|first=Naoum Iakovlevitch|last=Vilenkin|title=Special Functions and the Theory of Group Representations|series=Translations of Mathematical Monographs|volume=22|year=1968|publisher=American Mathematical Society| | |||
isbn=0-8218-1572-5}} | |||
*{{citation|first=Joachim|last=Weidmann|title=Spectral Theory of Ordinary Differential Operators|series=Lecture Notes in Mathematics|volume=1258| publisher=Springer-Verlag|year=1987|isbn=0-387-17902-X}} | |||
*{{citation|first=Hermann|last=[[Hermann Weyl|Weyl]]|title=Über gewöhnliche Differentialgleichungen mit Singularitäten und die zugehörigen Entwicklungen willkürlicher Functionen|journal=[[Mathematische Annalen]]|volume=68|year=1910|pages=220–269|doi=10.1007/BF01474161|url=http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=PPN235181684_0068&DMDID=DMDLOG_0023&L=1}} | |||
*{{citation|first=Hermann|last=Weyl|title=Über gewöhnliche Differentialgleichungen mit Singulären Stellen und ihre Eigenfunktionen| | |||
journal=Nachr. Akad. Wiss. Göttingen. Math.-Phys.|year=1910|pages=442–446}} | |||
*{{citation|first=Hermann|last=Weyl|title=Über das Pick-Nevanlinnasche Interpolationsproblem und sein infinitesimales Analogen|journal=Annals of Mathematics|year=1935|pages=230–254|doi=10.2307/1968677|volume=36|url=http://jstor.org/stable/1968677|issue=1|publisher=Annals of Mathematics}} | |||
[[Category:Ordinary differential equations]] | |||
[[Category:Operator theory]] | |||
[[Category:Spectral theory]] |
Latest revision as of 09:13, 29 October 2013
In mathematics, the spectral theory of ordinary differential equations is the part of spectral theory concerned with the determination of the spectrum and eigenfunction expansion associated with a linear ordinary differential equation. In his dissertation Hermann Weyl generalized the classical Sturm–Liouville theory on a finite closed interval to second order differential operators with singularities at the endpoints of the interval, possibly semi-infinite or infinite. Unlike the classical case, the spectrum may no longer consist of just a countable set of eigenvalues, but may also contain a continuous part. In this case the eigenfunction expansion involves an integral over the continuous part with respect to a spectral measure, given by the Titchmarsh–Kodaira formula. The theory was put in its final simplified form for singular differential equations of even degree by Kodaira and others, using von Neumann's spectral theorem. It has had important applications in quantum mechanics, operator theory and harmonic analysis on semisimple Lie groups.
Introduction
Spectral theory for second order ordinary differential equations on a compact interval was developed by Jacques Charles François Sturm and Joseph Liouville in the nineteenth century and is now known as Sturm–Liouville theory. In modern language it is an application of the spectral theorem for compact operators due to David Hilbert. In his dissertation, published in 1910, Hermann Weyl extended this theory to second order ordinary differential equations with singularities at the endpoints of the interval, now allowed to be infinite or semi-infinite. He simultaneously developed a spectral theory adapted to these special operators and introduced boundary conditions in terms of his celebrated dichotomy between limit points and limit circles.
In the 1920s John von Neumann established a general spectral theorem for unbounded self-adjoint operators, which Kunihiko Kodaira used to streamline Weyl's method. Kodaira also generalised Weyl's method to singular ordinary differential equations of even order and obtained a simple formula for the spectral measure. The same formula had also been obtained independently by E. C. Titchmarsh in 1946 (scientific communication between Japan and the United Kingdom had been interrupted by World War II). Titchmarsh had followed the method of the German mathematician Emil Hilb, who derived the eigenfunction expansions using complex function theory instead of operator theory. Other methods avoiding the spectral theorem were later developed independently by Levitan, Levinson and Yoshida, who used the fact that the resolvent of the singular differential operator could be approximated by compact resolvents corresponding to Sturm–Liouville problems for proper subintervals. Another method was found by Mark Grigoryevich Krein; his use of direction functionals was subsequently generalised by I. M. Glazman to arbitrary ordinary differential equations of even order.
Weyl applied his theory to Carl Friedrich Gauss's hypergeometric differential equation, thus obtaining a far-reaching generalisation of the transform formula of Gustav Ferdinand Mehler (1881) for the Legendre differential equation, rediscovered by the Russian physicist Vladimir Fock in 1943, and usually called the Mehler–Fock transform. The corresponding ordinary differential operator is the radial part of the Laplacian operator on 2-dimensional hyperbolic space. More generally, the Plancherel theorem for SL(2,R) of Harish Chandra and Gelfand–Naimark can be deduced from Weyl's theory for the hypergeometric equation, as can the theory of spherical functions for the isometry groups of higher dimensional hyperbolic spaces. Harish Chandra's later development of the Plancherel theorem for general real semisimple Lie groups was strongly influenced by the methods Weyl developed for eigenfunction expansions associated with singular ordinary differential equations. Equally importantly the theory also laid the mathematical foundations for the analysis of the Schrödinger equation and scattering matrix in quantum mechanics.
Solutions of ordinary differential equations
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Reduction to standard form
Let D be the second order differential operator on (a,b) given by
where p is a strictly positive continuously differentiable function and q and r are continuous real-valued functions.
For x0 in (a, b), define the Liouville transformation ψ by
Let U be the unitary operator (Uf)·ψ ψ'½ = f from L2 (a,b) onto L2(c,d), where c = ψ(a) and d = ψ(b). Then
where Q·ψ = q and R·ψ= (p' /2 + r)/p½. The term in g' can be removed using an Euler integrating factor. If S' /S = −R/2, then h = Sg satisfies
where the potential V is given by V = Q + S2/2 + S' /2. The differential operator can thus always be reduced to one of the form [1]
Existence theorem
The following is a version of the classical Picard existence theorem for second order differential equations with values in a Banach space E.[2]
Let α, β be arbitrary elements of E, A a bounded operator on E and q a continuous function on [a,b].
Then, for c = a or b, the differential equation
- Df = Af
has a unique solution f in C2([a,b],E) satisfying the initial conditions
- f(c) = β, f '(c) = α.
In fact a solution of the differential equation with these initial conditions is equivalent to a solution of the integral equation
- f = h + T f
with T the bounded linear map on C([a,b], E) defined by
where K is the Volterra kernel
- K(x,t)= (x − t)(q(t) − A)
and
- h(x) = α(x − c) + β.
Since ||Tk|| tends to 0, this integral equation has a unique solution given by the Neumann series
- f = (I − T)−1 h = h + T h + T2 h + T3 h + ···
This iterative scheme is often called Picard iteration after the French mathematician Charles Émile Picard.
Fundamental eigenfunctions
If f is twice continuously differentiable (i.e. C2) on (a, b) satisfying Df = λf, then f is called an eigenfunction of L with eigenvalue λ.
- In the case of a compact interval [a, b] and q continuous on [a, b], the existence theorem implies that for c = a or b and every complex number λ there a unique C2 eigenfunction fλ on [a, b] with fλ(c) and f 'λ(c) prescribed. Moreover, for each x in [a, b], fλ(x) and f 'λ(x) are holomorphic functions of λ.
- For an arbitrary interval (a,b) and q continuous on (a, b), the existence theorem implies that for c in (a, b) and every complex number λ there a unique C2 eigenfunction fλ on (a, b) with fλ(c) and f 'λ(c) prescribed. Moreover, for each x in (a, b), fλ(x) and f 'λ(x) are holomorphic functions of λ.
Green's formula
If f and g are C2 functions on (a, b), the Wronskian W(f, g) is defined by
- W(f, g) (x) = f(x) g '(x) − f '(x) g(x).
Green's formulaTemplate:Disambiguation needed states that for x, y in (a, b)
When q is continuous and f, g C2 on the compact interval [a, b], this formula also holds for x = a or y = b.
When f and g are eigenfunctions for the same eigenvalue, then
so that W(f, g) is independent of x.
Classical Sturm–Liouville theory
Mining Engineer (Excluding Oil ) Truman from Alma, loves to spend time knotting, largest property developers in singapore developers in singapore and stamp collecting. Recently had a family visit to Urnes Stave Church. Let [a, b] be a finite closed interval, q a real-valued continuous function on [a, b] and let H0 be the space of C2 functions f on [a, b] satisfying the mixed boundary conditions
with inner product
In practise usually one of the two unmixed boundary conditions:
- Dirichlet boundary condition f(c) = 0
- Neumann boundary condition f '(c) = 0
is imposed at each endpoint c = a, b.
The differential operator D given by
acts on H0. A function f in H0 is called an eigenfunction of D (for the above choice of boundary values) if Df = λ f for some complex number λ, the corresponding eigenvalue. By Green's formula, D is formally self-adjoint on H0:
- (Df, g) = (f, Dg) for f, g in H0.
As a consequence, exactly as for a self-adjoint matrix in finite dimensions,
- the eigenvalues of D are real;
- the eigenspaces for distinct eigenvalues are orthogonal.
It turns out that the eigenvalues can be described by the maximum-minimum principle of Rayleigh–Ritz [3] (see below). In fact it is easy to see a priori that the eigenvalues are bounded below because the operator D is itself bounded below on H0:
In fact integrating by parts
For unmixed boundary conditions, the first term vanishes and the inequality holds with M = inf q.
In the mixed case the first term can be estimated using an elementary Peter-Paul version of Sobolev's inequality:
- "Given ε > 0, there is constant R >0 such that |f(x)|2 ≤ ε (f', f') + R (f, f) for all f in C1[a, b]."
In fact, since
- |f(b) − f(x)| ≤ (b − a)½·||f '||2,
only an estimate for f(b) is needed and this follows by replacing f(x) in the above inequality by (x − a)n·(b − a)−n·f(x) for n sufficiently large.
Green's function (regular case)
From the theory of ordinary differential equations, there are unique fundamental eigenfunctions φλ(x), χλ(x) such that
- D φλ = λ φλ, φλ(a) = sin α, φλ'(a) = cos α
- D χλ = λ χλ, χλ(b) = sin β, χλ'(b) = cos β
which at each point, together with their first derivatives, depend holomorphically on λ. Let
- ω(λ) = W(φλ, χλ),
an entire holomorphic function.
This function ω(λ) plays the rôle of the characteristic polynomial of D. Indeed the uniqueness of the fundamental eigenfunctions implies that its zeros are precisely the eigenvalues of D and that each non-zero eigenspace is one-dimensional. In particular there are at most countably many eigenvalues of D and, if there are infinitely many, they must tend to infinity. It turns out that the zeros of ω(λ) also have mutilplicity one (see below).
If λ is not an eigenvalue of D on H0, define the Green's function by
- Gλ(x,y) = φλ (x) χλ(y) / ω(λ) for x ≥ y and χλ(x) φλ (y) / ω(λ) for y ≥ x.
This kernel defines an operator on the inner product space C[a,b] via
Since Gλ(x,y) is continuous on [a, b] x [a, b], it defines a Hilbert–Schmidt operator on the Hilbert space completion H of C[a, b] = H1 (or equivalently of the dense subspace H0), taking values in H1. This operator carries H1 into H0. When λ is real, Gλ(x,y) = Gλ(y,x) is also real, so defines a self-adjoint operator on H. Moreover
- Gλ (D − λ) =I on H0
- Gλ carries H1 into H0, and (D − λ) Gλ = I on H1.
Thus the operator Gλ can be identified with the resolvent (D − λ)−1.
Spectral theorem
Theorem. The eigenvalues of D are real of multiplicity one and form an increasing sequence λ1 < λ2 < ··· tending to infinity.
The corresponding normalised eigenfunctions form an orthonormal basis of H0.
The kth eigenvalue of D is given by the minimax principle
In particular if q1 ≤ q2, then
In fact let T = Gλ for λ large and negative. Then T defines a compact self-adjoint operator on the Hilbert space H. By the spectral theorem for compact self-adjoint operators, H has an orthonormal basis consisting of eigenvectors ψn of T with Tψn = μn ψn, where μn tends to zero. The range of T contains H0 so is dense. Hence 0 is not an eigenvector of T. The resolvent properties of T imply that ψn lies in H0 and that
- D ψn = (λ + 1/μn) ψn
The minimax principle follows because if
then λ(G)= λk for the linear span of the first k − 1 eigenfunctions. For any other (k − 1)-dimensional subspace G, some f in the linear span of the first k eigenvectors must be orthogonal to G. Hence λ(G) ≤ (Df,f)/(f,f) ≤ λk.
Wronskian as a Fredholm determinant
For simplicity, suppose that m ≤ q(x) ≤ M on [0,π] with Dirichlet boundary conditions. The minimax principle shows that
It follows that the resolvent (D − λ)−1 is a trace-class operator whenever λ is not an eigenvalue of D and hence that the Fredholm determinant det I − μ(D − λ)−1 is defined.
The Dirichlet boundary conditions imply that
- ω(λ)= φλ(b).
Using Picard iteration, Titchmarsh showed that φλ(b), and hence ω(λ), is an entire function of finite order 1/2:
- ω(λ) = O(e√|λ|)
At a zero μ of ω(λ), φμ(b) = 0. Moreover
satisfies (D − μ)ψ = φμ. Thus
- ω(λ) = (λ − μ)ψ(b) + O( (λ − μ)2).
This implies that[4]
- μ is a simple zero of ω(λ).
For otherwise ψ(b) = 0, so that ψ would have to lie in H0. But then
- (φμ, φμ) = ((D − μ)ψ, φμ) = (ψ, (D − μ)φμ) = 0,
a contradiction.
On the other hand the distribution of the zeros of the entire function ω(λ) is already known from the minimax principle.
By the Hadamard factorization theorem, it follows that[5]
for some non-zero constant C.
Hence
In particular if 0 is not an eigenvalue of D
Tools from abstract spectral theory
Functions of bounded variation
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A function ρ(x) of bounded variation[6] on a closed interval [a, b] is a complex-valued function such that
its total variation V(ρ), the supremum
of the variations
over all dissections
is finite. The real and imaginary parts of ρ are real-valued functions of bounded variation. If ρ is real-valued and normalised so that ρ(a)=0, it has a canonical decomposition as the difference of two bounded non-decreasing functions:
where ρ+(x) and ρ–(x) are the total positive and negative variation of ρ over [a, x].
If f is a continuous function on [a, b] its Riemann–Stieltjes integral with respect to ρ
is defined to be the limit of approximating sums
as the mesh of the dissection, given by sup |xr+1 - xr|, tends to zero.
This integral satisfies
and thus defines a bounded linear functional dρ on C[a, b] with norm ||dρ||=V(ρ).
Every bounded linear functional μ on C[a, b] has an absolute value |μ| defined for non-negative f by[7]
The form |μ| extends linearly to a bounded linear form on C[a, b] with norm ||μ|| and satisfies the characterizing inequality
- |μ(f)| ≤ |μ|(|f|)
for f in C[a, b]. If μ is real, i.e. is real-valued on real-valued functions, then
gives a canonical decomposition as a difference of positive forms, i.e. forms that are non-negative on non-negative functions.
Every positive form μ extends uniquely to the linear span of non-negative bounded lower semicontinuous functions g by the formula[8]
where the non-negative continuous functions fn increase pointwise to g.
The same therefore applies to an arbitrary bounded linear form μ, so that a function ρ of bounded variation may be defined by[9]
where χA denotes the characteristic function of a subset A of [a, b]. Thus μ = dρ and ||μ|| = ||dρ||. Moreover μ+ = dρ+ and μ– = dρ–.
This correspondence between functions of bounded variation and bounded linear forms is a special case of the Riesz representation theorem.
The support of μ = dρ is the complement of all points x in [a,b] where ρ is constant on some neighborhood of x; by definition it is a closed subset A of [a,b]. Moreover μ((1-χA)f) =0, so that μ(f) = 0 if f vanishes on A.
Spectral measure
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We will not only get you a property at a rock-backside price but also in an space that you've got longed for. You simply must chill out back after giving us the accountability. We will assure you 100% satisfaction. Since we now have been working in the Singapore actual property market for a very long time, we know the place you may get the best property at the right price. You will also be extremely benefited by choosing us, as we may even let you know about the precise time to invest in the Singapore actual property market.
The Hexacube is offering new ec launch singapore business property for sale Singapore investors want to contemplate. Residents of the realm will likely appreciate that they'll customize the business area that they wish to purchase as properly. This venture represents one of the crucial expansive buildings offered in Singapore up to now. Many investors will possible want to try how they will customise the property that they do determine to buy by means of here. This location has offered folks the prospect that they should understand extra about how this course of can work as well.
Singapore has been beckoning to traders ever since the value of properties in Singapore started sky rocketing just a few years again. Many businesses have their places of work in Singapore and prefer to own their own workplace area within the country once they decide to have a everlasting office. Rentals in Singapore in the corporate sector can make sense for some time until a business has discovered a agency footing. Finding Commercial Property Singapore takes a variety of time and effort but might be very rewarding in the long term.
is changing into a rising pattern among Singaporeans as the standard of living is increasing over time and more Singaporeans have abundance of capital to invest on properties. Investing in the personal properties in Singapore I would like to applaud you for arising with such a book which covers the secrets and techniques and tips of among the profitable Singapore property buyers. I believe many novice investors will profit quite a bit from studying and making use of some of the tips shared by the gurus." – Woo Chee Hoe Special bonus for consumers of Secrets of Singapore Property Gurus Actually, I can't consider one other resource on the market that teaches you all the points above about Singapore property at such a low value. Can you? Condominium For Sale (D09) – Yong An Park For Lease
In 12 months 2013, c ommercial retails, shoebox residences and mass market properties continued to be the celebrities of the property market. Models are snapped up in report time and at document breaking prices. Builders are having fun with overwhelming demand and patrons need more. We feel that these segments of the property market are booming is a repercussion of the property cooling measures no.6 and no. 7. With additional buyer's stamp responsibility imposed on residential properties, buyers change their focus to commercial and industrial properties. I imagine every property purchasers need their property funding to understand in value.
Let H be a Hilbert space and T a self-adjoint bounded operator on H with 0 ≤ T ≤ I, so that the spectrum σ(T) of T is contained in [0,1]. If p(t) is a complex polynomial, then by the spectral mapping theorem
- σ(p(T)) = p(σ(T))
and hence
- ||p(T)|| ≤ ||p||∞,
where ||·||∞ denotes the uniform norm on C[0,1]. By the Weierstrass approximation theorem, polynomials are uniformly dense in C[0, 1]. It follows that f(T) can be defined for every f in C[0,1], with
- σ(f(T)) = f(σ(T)) and ||f(T)|| ≤ ||f||∞.
If 0 ≤ g ≤ 1 is a lower semicontinuous function on [0,1], for example the characteristic function χ[0,α] of a subinterval of [0,1], then g is a pointwise increasing limit of non-negative fn in C[0,1].
According to Sz.-Nagy,[10] if ξ is a vector in H, then the vectors
- ηn = fn(T) ξ
form a Cauchy sequence in H, since, for n ≥ m,
and (ηn,ξ) = (fn(T)ξ, ξ) is bounded and increasing, so has a limit.
It follows that g(T) can be defined by[11]
- g(T)ξ = lim fn(T)ξ.
If ξ and η are vectors in H, then
defines a bounded linear form μξ,η on H. By the Riesz representation theorem
for a unique normalised function ρξ,η of bounded variation on [0,1].
dρξ,η (or sometimes slightly incorrectly ρξ,η itself) is called the spectral measure determined by ξ and η.
The operator g(T) is accordingly uniquely characterised by the equation
The spectral projection E(λ) is defined by
so that
It follows that
which is understood in the sense that for any vectors ξ and η,
For a single vector ξ, μξ = μξ,ξ is a positive form on [0,1] (in other words proportional to a probability measure on [0,1]) and ρξ = ρξ,ξ is non-negative and non-decreasing. Polarisation shows that all the forms μξ,η can naturally be expressed in terms of such positive forms, since
- μξ,η = ¼(μξ+η + i μξ+iη − μξ−η −i μξ−iη).
If the vector ξ is such that the linear span of the vectors (Tnξ) is dense in H, i.e. ξ is a cyclic vector for T, then the map U defined by
satisfies
Let L2([0,1], dρξ) denote the Hilbert space completion of C[0,1] associated with the possibly degenerate inner product on the right hand side.[12] Thus U extends to a unitary transformation of L2([0,1], dρξ) onto H. UTU* is then just multiplication by λ on L2([0,1], dρξ); and more generally Uf(T)U* is multiplication by f(λ). In this case, the support of dρξ is exactly σ(T), so that
- the self-adjoint operator becomes a multiplication operator on the space of functions on its spectrum with inner product given by the spectral measure.
Weyl–Titchmarsh–Kodaira theory
The eigenfunction expansion associated with singular differential operators of the form
on an open interval (a, b) requires an initial analysis of the behaviour of the fundamental eigenfunctions near the endpoints a and b to determine possible boundary conditions there. Unlike the regular Sturm–Liouville case, in some circumstances spectral values of D can have multiplicity 2. In the development outlined below standard assumptions will be imposed on p and q that guarantee that the spectrum of D has multiplicity one everywhere and is bounded below. This includes almost all important applications; modifications required for the more general case will be discussed later.
Having chosen the boundary conditions, as in the classical theory the resolvent of D, (D + R )−1 for R large and positive, is given by an operator T corresponding to a Green's function constructed from two fundamental eigenfunctions. In the classical case T was a compact self-adjoint operator; in this case T is just a self-adjoint bounded operator with 0 ≤ T ≤ I. The abstract theory of spectral measure can therefore be applied to T to give the eigenfunction expansion for D.
The central idea in the proof of Weyl and Kodaira can be explained informally as follows. Assume that the spectrum of D lies in [1,∞) and that T =D−1 and let
be the spectral projection of D corresponding to the interval [1,λ]. For an arbitrary function f define
f(x,λ) may be regarded as a differentiable map into the space of functions of bounded variation ρ; or equivalently as a differentiable map
into the Banach space E of bounded linear functionals dρ on C[α,β] whenever [α,β] is a compact subinterval of [1, ∞).
Weyl's fundamental observation was that dλ f satisfies a second order ordinary differential equation taking values in E:
After imposing initial conditions on the first two derivatives at a fixed point c, this equation can be solved explicitly in terms of the two fundamental eigenfunctions and the "initial value" functionals
This point of view may now be turned on its head: f(c,λ) and fx(c,λ) may be written as
where ξ1(λ) and ξ2(λ) are given purely in terms of the fundamental eigenfunctions. The functions of bounded variation
determine a spectral measure on the spectrum of D and can be computed explicitly from the behaviour of the fundamental eigenfunctions (the Titchmarsh–Kodaira formula).
Limit circle and limit point for singular equations
Let q(x) be a continuous real-valued function on (0,∞) and let D be the second order differential operator
on (0,∞). Fix a point c in (0,∞) and, for λ complex, let be the unique fundamental eigenfunctions of D on (0,∞) satisfying
together with the initial conditions at c
Then their Wronskian satisfies
since it is constant and equal to 1 at c.
If λ is non-real and 0 < x < ∞, then Green's formula implies
This defines a circle in the complex μ-plane, the interior of which is given by
if x > c and by
if x < c.
Let Dx be the closed disc enclosed by the circle. By definition these closed discs are nested and decrease as x approaches 0 or ∞. So in the limit, the circles tend either to a limit circle or a limit point at each end. In particular if μ is a limit point or a point on the limit circle at 0 or ∞, then is square integrable (L2) near 0 or ∞. In particular:[13]
- there are always non-zero solutions of Df = λf which are square integrable near 0 or ∞;
- there is exactly one non-zero solution (up to scalar multiples) of Df = λf which is square integrable near 0 or ∞ precisely in the limit point case.
On the other hand if Dg = λ' g for another value λ', then
satisfies Dh = λh, so that
Using this to estimate g, it follows that[13]
- the limit point/limit circle behaviour at 0 or ∞ is independent of the choice of λ.
More generally if Dg= (λ – r) g for some function r(x), then[14]
From this it follows that[14]
- if r is continuous at 0, then D + r is limit point or limit circle at 0 precisely when D is,
so that in particular[15]
- if q(x)- a/x2 is continuous at 0, then D is limit point at 0 if and only if a ≥ ¾.
Similarly
- if r has a finite limit at ∞, then D + r is limit point or limit circle at ∞ precisely when D is,
so that in particular[16]
- if q has a finite limit at ∞, then D is limit point at ∞.
Many more elaborate criteria to be limit point or limit circle can be found in the mathematical literature.
Green's function (singular case)
Consider the differential operator
on (0,∞) with q0 positive and continuous on (0,∞) and p0 continuously differentiable in [0,∞), positive in (0,∞) and p0(0)=0.
Moreover assume that after reduction to standard form D0 becomes the equivalent operator
on (0,∞) where q has a finite limit at ∞. Thus
- D is limit point at ∞.
At 0, D may be either limit circle or limit point. In either case there is an eigenfunction Φ0 with DΦ0=0 and Φ0 square integrable near 0. In the limit circle case, Φ0 determines a boundary condition at 0:
For λ complex, let Φλ and Χλ satisfy
- (D – λ)Φλ = 0, (D – λ)Χλ = 0
- Χλ square integrable near infinity
- Φλ square integrable at 0 if 0 is limit point
- Φλ satisfies the boundary condition above if 0 is limit circle.
Let
a constant which vanishes precisely when Φλ and Χλ are proportional, i.e. λ is an eigenvalue of D for these boundary conditions.
On the other hand, this cannot occur if Im λ ≠ 0 or if λ is negative.[13]
Indeed if D f= λf with q0 – λ ≥ δ >0, then by Green's formula (Df,f) = (f,Df), since W(f,f*) is constant. So λ must be real. If f is taken to be real-valued in the D0 realization, then for 0 < x < y
Since p0(0) = 0 and f is integrable near 0, p0f f ' must vanish at 0. Setting x = 0, it follows that f(y) f '(y) >0, so that f2 is increasing, contradicting the square integrability of f near ∞.
Thus, adding a positive scalar to q, it may be assumed that
- ω(λ) ≠ 0 when λ is not in [1,∞).
If ω(λ) ≠ 0, the Green's function Gλ(x,y) at λ is defined by
and is independent of the choice of λ and Χλ.
In the examples there will be a third "bad" eigenfunction Ψλ defined and holomorphic for λ not in [1, ∞) such that Ψλ satisfies the boundary conditions at neither 0 nor ∞. This means that for λ not in [1, ∞)
- W(Φλ,Ψλ) is nowhere vanishing;
- W(Χλ,Ψλ) is nowhere vanishing.
In this case Χλ is proportional to Φλ + m(λ) Ψλ, where
- m(λ) = – W(Φλ,Χλ) / W(Ψλ,Χλ).
Let H1 be the space of square integrable continuous functions on (0,∞) and let H0 be
- the space of C2 functions f on (0,∞) of compact support if D is limit point at 0
- the space of C2 functions f on (0,∞) with W(f,Φ0)=0 at 0 and with f = 0 near ∞ if D is limit circle at 0.
Define T = G0 by
Then T D = I on H0, D T = I on H1 and the operator D is bounded below on H0:
Thus T is a self-adjoint bounded operator with 0 ≤ T ≤ I.
Formally T = D−1. The corresponding operators Gλ defined for λ not in [1,∞) can be formally identified with
and satisfy Gλ (D – λ) = I on H0, (D – λ)Gλ = I on H1.
Spectral theorem and Titchmarsh–Kodaira formula
Theorem.[13][17][18] For every real number λ let ρ(λ) be defined by the Titchmarsh–Kodaira formula:
Then ρ(λ) is a lower semicontinuous non-decreasing function of λ and if
then U defines a unitary transformation of L2(0,∞) onto L2([1,∞), dρ) such that UDU−1 corresponds to multiplication by λ.
The inverse transformation U−1 is given by
The spectrum of D equals the support of dρ.
Kodaira gave a streamlined version[19][20] of Weyl's original proof.[13] (M.H. Stone had previously shown[21] how part of Weyl's work could be simplified using von Neumann's spectral theorem.)
In fact for T =D−1 with 0 ≤ T ≤ I, the spectral projection E(λ) of T is defined by
It is also the spectral projection of D corresponding to the interval [1,λ].
For f in H1 define
f(x,λ) may be regarded as a differentiable map into the space of functions ρ of bounded variation; or equivalently as a differentiable map
into the Banach space E of bounded linear functionals dρ on C[α,β] for any compact subinterval [α,β] of [1, ∞).
The functionals (or measures) dλ f(x) satisfies the following E-valued second order ordinary differential equation:
with initial conditions at c in (0,∞)
If φλ and χλ are the special eigenfunctions adapted to c, then
Moreover
where
with
(As the notation suggests, ξλ(0) and ξλ(1) do not depend on the choice of z.)
Setting
it follows that
On the other hand there are holomorphic functions a(λ), b(λ) such that
- φλ + a(λ) χλ is proportional to Φλ;
- φλ + b(λ) χλ is proportional to Χλ.
Since W(φλ,χλ) = 1, the Green's function is given by
Direct calculation[22] shows that
where the so-called characteristic matrix Mij(z) is given by
Hence
which immediately implies
(This is a special case of the "Stietljes inversion formula".)
Setting ψλ(0)=φλ and ψλ(1)=χλ, it follows that
This identity is equivalent to the spectral theorem and Titchmarsh–Kodaira formula.
Application to the hypergeometric equation
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Singapore has been beckoning to traders ever since the value of properties in Singapore started sky rocketing just a few years again. Many businesses have their places of work in Singapore and prefer to own their own workplace area within the country once they decide to have a everlasting office. Rentals in Singapore in the corporate sector can make sense for some time until a business has discovered a agency footing. Finding Commercial Property Singapore takes a variety of time and effort but might be very rewarding in the long term.
is changing into a rising pattern among Singaporeans as the standard of living is increasing over time and more Singaporeans have abundance of capital to invest on properties. Investing in the personal properties in Singapore I would like to applaud you for arising with such a book which covers the secrets and techniques and tips of among the profitable Singapore property buyers. I believe many novice investors will profit quite a bit from studying and making use of some of the tips shared by the gurus." – Woo Chee Hoe Special bonus for consumers of Secrets of Singapore Property Gurus Actually, I can't consider one other resource on the market that teaches you all the points above about Singapore property at such a low value. Can you? Condominium For Sale (D09) – Yong An Park For Lease
In 12 months 2013, c ommercial retails, shoebox residences and mass market properties continued to be the celebrities of the property market. Models are snapped up in report time and at document breaking prices. Builders are having fun with overwhelming demand and patrons need more. We feel that these segments of the property market are booming is a repercussion of the property cooling measures no.6 and no. 7. With additional buyer's stamp responsibility imposed on residential properties, buyers change their focus to commercial and industrial properties. I imagine every property purchasers need their property funding to understand in value.
The Mehler–Fock transform[23][24][25] concerns the eigenfunction expansion associated with the Legendre differential operator D
on (1,∞). The eigenfunctions are the Legendre functions[26]
with eigenvalue λ ≥ 0. The two Mehler–Fock transformations are[27]
and
(Often this is written in terms of the variable τ = √λ.)
Mehler and Fock studied this differential operator because it arose as the radial component of the Laplacian on 2-dimensional hyperbolic space. More generally,[28] consider the group G = SU(1,1) consisting of complex matrices of the form
with determinant |α|2 − |β|2 = 1.
Application to the hydrogen atom
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We will not only get you a property at a rock-backside price but also in an space that you've got longed for. You simply must chill out back after giving us the accountability. We will assure you 100% satisfaction. Since we now have been working in the Singapore actual property market for a very long time, we know the place you may get the best property at the right price. You will also be extremely benefited by choosing us, as we may even let you know about the precise time to invest in the Singapore actual property market.
The Hexacube is offering new ec launch singapore business property for sale Singapore investors want to contemplate. Residents of the realm will likely appreciate that they'll customize the business area that they wish to purchase as properly. This venture represents one of the crucial expansive buildings offered in Singapore up to now. Many investors will possible want to try how they will customise the property that they do determine to buy by means of here. This location has offered folks the prospect that they should understand extra about how this course of can work as well.
Singapore has been beckoning to traders ever since the value of properties in Singapore started sky rocketing just a few years again. Many businesses have their places of work in Singapore and prefer to own their own workplace area within the country once they decide to have a everlasting office. Rentals in Singapore in the corporate sector can make sense for some time until a business has discovered a agency footing. Finding Commercial Property Singapore takes a variety of time and effort but might be very rewarding in the long term.
is changing into a rising pattern among Singaporeans as the standard of living is increasing over time and more Singaporeans have abundance of capital to invest on properties. Investing in the personal properties in Singapore I would like to applaud you for arising with such a book which covers the secrets and techniques and tips of among the profitable Singapore property buyers. I believe many novice investors will profit quite a bit from studying and making use of some of the tips shared by the gurus." – Woo Chee Hoe Special bonus for consumers of Secrets of Singapore Property Gurus Actually, I can't consider one other resource on the market that teaches you all the points above about Singapore property at such a low value. Can you? Condominium For Sale (D09) – Yong An Park For Lease
In 12 months 2013, c ommercial retails, shoebox residences and mass market properties continued to be the celebrities of the property market. Models are snapped up in report time and at document breaking prices. Builders are having fun with overwhelming demand and patrons need more. We feel that these segments of the property market are booming is a repercussion of the property cooling measures no.6 and no. 7. With additional buyer's stamp responsibility imposed on residential properties, buyers change their focus to commercial and industrial properties. I imagine every property purchasers need their property funding to understand in value.
Generalisations and alternative approaches
A Weyl function can be defined at a singular endpoint giving rise to a singular version of Weyl–Titchmarsh–Kodaira theory.[29] this applies for example to the case of radial Schrödinger operators
The whole theory can also be extended to the case where the coefficients are allowed to be measures.[30]
Gelfand–Levitan theory
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We will not only get you a property at a rock-backside price but also in an space that you've got longed for. You simply must chill out back after giving us the accountability. We will assure you 100% satisfaction. Since we now have been working in the Singapore actual property market for a very long time, we know the place you may get the best property at the right price. You will also be extremely benefited by choosing us, as we may even let you know about the precise time to invest in the Singapore actual property market.
The Hexacube is offering new ec launch singapore business property for sale Singapore investors want to contemplate. Residents of the realm will likely appreciate that they'll customize the business area that they wish to purchase as properly. This venture represents one of the crucial expansive buildings offered in Singapore up to now. Many investors will possible want to try how they will customise the property that they do determine to buy by means of here. This location has offered folks the prospect that they should understand extra about how this course of can work as well.
Singapore has been beckoning to traders ever since the value of properties in Singapore started sky rocketing just a few years again. Many businesses have their places of work in Singapore and prefer to own their own workplace area within the country once they decide to have a everlasting office. Rentals in Singapore in the corporate sector can make sense for some time until a business has discovered a agency footing. Finding Commercial Property Singapore takes a variety of time and effort but might be very rewarding in the long term.
is changing into a rising pattern among Singaporeans as the standard of living is increasing over time and more Singaporeans have abundance of capital to invest on properties. Investing in the personal properties in Singapore I would like to applaud you for arising with such a book which covers the secrets and techniques and tips of among the profitable Singapore property buyers. I believe many novice investors will profit quite a bit from studying and making use of some of the tips shared by the gurus." – Woo Chee Hoe Special bonus for consumers of Secrets of Singapore Property Gurus Actually, I can't consider one other resource on the market that teaches you all the points above about Singapore property at such a low value. Can you? Condominium For Sale (D09) – Yong An Park For Lease
In 12 months 2013, c ommercial retails, shoebox residences and mass market properties continued to be the celebrities of the property market. Models are snapped up in report time and at document breaking prices. Builders are having fun with overwhelming demand and patrons need more. We feel that these segments of the property market are booming is a repercussion of the property cooling measures no.6 and no. 7. With additional buyer's stamp responsibility imposed on residential properties, buyers change their focus to commercial and industrial properties. I imagine every property purchasers need their property funding to understand in value.
Notes
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
References
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
- 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
- ↑ Template:Harvnb
- ↑ Template:Harvnb, Chapter X.
- ↑ Template:Harvnb
- ↑ Template:Harvnb
- ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010, §8.2. - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010, page 40. - ↑ Template:Harvnb
- ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Template:Harvnb
- ↑ This is a limit in the strong operator topology.
- ↑ A bona fide inner product is defined on the quotient by the subspace of null functions f, i.e. those with μξ(|f|2)=0. Alternatively in this case the support of the measure is σ(T), so the right hand side defines a (non-degenerate) inner product on C(σ(T)).
- ↑ 13.0 13.1 13.2 13.3 13.4 Template:Harvnb
- ↑ 14.0 14.1 Template:Harvnb
- ↑ Template:Harvnb
- ↑ Template:Harvnb
- ↑ Template:Harvnb, Chapter III.
- ↑ Template:Harvnb
- ↑ Template:Harvnb; for omitted details, see Template:Harvnb
- ↑ Template:Harvnb
- ↑ Template:Harvnb, Chapter X.
- ↑ Template:Harvnb
- ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Template:Harvnb
- ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Template:Harvnb, Chapter VI.
- ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010