|
|
| Line 1: |
Line 1: |
| In [[quantum physics]], '''Regge theory''' is the study of the analytic properties of [[scattering]] as a function of [[angular momentum#Angular_momentum_in_quantum_mechanics|angular momentum]], where the angular momentum is not restricted to be an integer but is allowed to take any [[complex number|complex value]]. The nonrelativistic theory was developed by [[Tullio Regge]] in 1957.
| | They call me Emilia. South Dakota is her beginning place but she needs to move because of her family members. What I adore doing is playing baseball but I haven't produced a dime with it. Supervising is my occupation.<br><br>my weblog [http://Lordk.at/healthyfooddelivery98296 weight loss food delivery] |
| | |
| ==History and implications==
| |
| The main result of the theory is that the scattering amplitude for potential scattering grows as a function of the cosine <math>z</math> of the scattering angle as a power that changes as the scattering energy changes:
| |
| :<math>
| |
| A(z) \propto z^{l(E^2)}
| |
| </math>
| |
| where <math>l(E^2)</math> is the noninteger value of the angular momentum of a would-be bound state with energy <math>E</math>. It is determined by solving the radial Schrödinger equation and it smoothly interpolates the energy of wavefunctions with different angular momentum but with the same [[radial excitation number]]. The trajectory function is a function of <math>s=E^2</math> for relativistic generalization. The expression <math>l(s)</math> is known as the Regge trajectory function, and when it is an integer, the particles form an actual bound state with this angular momentum. The asymptotic form applies when <math>z</math> much greater than one, which is not a physical limit in nonrelativistic scattering.
| |
| | |
| Shortly afterwards, [[Stanley Mandelstam]] noted that in relativity the purely formal limit of <math>z</math> large is near to a physical limit — the limit of large <math>t</math>. Large <math>t</math> means large energy in the crossed channel, where one of the incoming particles has an energy momentum that makes it an energetic outgoing antiparticle. This observation turned Regge theory from a mathematical curiosity into a physical theory: it demands that the function that determines the falloff rate of the scattering amplitude for particle-particle scattering at large energies is the same as the function that determines the bound state energies for a particle-antiparticle system as a function of angular momentum.<ref>{{cite book|first1=V.|last1=Gribov|title=The Theory of Complex Angular Momentum|year=2003| isbn=0-521-81834-6| bibcode=2003tcam.book.....G|publisher=Cambridge University press}}</ref>
| |
| | |
| The switch required swapping the [[Mandelstam variables|Mandelstam variable]] <math>s</math>, which is the square of the energy, for <math>t</math>, which is the squared momentum transfer, which for elastic soft collisions of identical particles is s times one minus the cosine of the scattering angle. The relation in the crossed channel becomes
| |
| :<math> | |
| A(z) \propto s^{l(t)}
| |
| </math>
| |
| | |
| ...which says that the amplitude has a different power law falloff as a function of energy at different corresponding angles, where corresponding angles are those with the same value of <math>t</math>. It predicts that the function that determines the [[power law]] is the same function that interpolates the energies where the resonances appear. The range of angles where scattering can be productively described by Regge theory shrinks into a narrow cone around the beam-line at large energies.
| |
| | |
| In 1960 [[Geoffrey Chew]] and [[Steven Frautschi]] conjectured from limited data that the strongly interacting particles had a very simple dependence of the squared-mass on the angular momentum: the particles fall into families where the Regge trajectory functions were straight lines: <math>l(s)=ks</math> with the same constant <math>k</math> for all the trajectories. The straight-line Regge trajectories were later understood as arising from massless endpoints on rotating relativistic strings. Since a Regge description implied that the particles were bound states, Chew and Frautschi concluded that none of the strongly interacting particles were elementary.
| |
| | |
| Experimentally, the near-beam behavior of scattering did fall off with angle as explained by Regge theory, leading many to accept that the particles in the strong interactions were composite. Much of the scattering was ''diffractive'', meaning that the particles hardly scatter at all — staying close to the beam line after the collision. [[Vladimir Gribov]] noted that the [[Froissart bound]] combined with the assumption of maximum possible scattering implied there was a Regge trajectory that would lead to logarithmically rising cross sections, a trajectory nowadays known as the [[Pomeron]]. He went on to formulate a [[Reggeon field theory|quantitative perturbation theory]] for near beam line scattering dominated by multi-Pomeron exchange.
| |
| | |
| From the fundamental observation that hadrons are composite, there grew two points of view. Some correctly advocated that there were elementary particles, nowadays called quarks and gluons, which made a quantum field theory in which the hadrons were bound states. Others also correctly believed that it was possible to formulate a theory without elementary particles — where all the particles were bound states lying on Regge trajectories and scatter self-consistently. This was called [[S-matrix theory]].
| |
| | |
| The most successful S-matrix approach centered on the narrow-resonance approximation, the idea that there is a consistent expansion starting from stable particles on straight-line Regge trajectories. After many false starts, Dolen Horn and Schmidt understood a crucial property that led [[Gabriele Veneziano]] to formulate a self-consistent scattering amplitude, the first [[string theory]]. Mandelstam noted that the limit where the regge trajectories are straight is also the limit where the lifetime of the states is long.
| |
| | |
| As a fundamental theory of [[strong interaction]]s at high energies, Regge theory enjoyed a period of interest in the 1960s, but it was largely succeeded by [[quantum chromodynamics]]. As a phenomenological theory, it is still an indispensable tool for understanding near-beam line scattering and scattering at very large energies. Modern research focuses both on the connection to perturbation theory and to string theory.
| |
| | |
| {{unsolved|physics|How does Regge theory emerge from quantum chromodynamics at long distances?}}
| |
| | |
| ==See also==
| |
| *[[Pomeron]]
| |
| *[[S-matrix theory]]
| |
| *[[Faber–Jackson relation]]
| |
| *[[Plasma cosmology]]
| |
| *[[Quark–gluon plasma]]
| |
| *[[Dual resonance model]]
| |
| | |
| ==References==
| |
| {{Reflist}}
| |
| | |
| ==Further reading==
| |
| * {{cite book
| |
| |first1=P. D. B.
| |
| |last1=Collins
| |
| |title=An Introduction to Regge Theory and High-Energy Physics
| |
| |location=Cambridge
| |
| |publisher=Cambridge University Press
| |
| |year=1977
| |
| |isbn=0-521-21245-6
| |
| }}
| |
| * {{cite journal
| |
| |first1=R. J.
| |
| |last1=Eden
| |
| |title=Regge poles and elementary particles
| |
| |journal=Rep. Prog. Phys.
| |
| |volume=34
| |
| |issue=3
| |
| |doi=10.1088/0034-4885/34/3/304
| |
| |pages=995–1053
| |
| |year=1971
| |
| |bibcode=1971RPPh...34..995E
| |
| }}
| |
| * {{cite journal
| |
| |first1=A. C.
| |
| |last1=Irving
| |
| |first2=R. P.
| |
| |last2=Worden
| |
| |title=Regge phenomenology
| |
| |journal=Phys. Rep.
| |
| |volume=34
| |
| |issue=3
| |
| |bibcode=1977PhR....34..117I
| |
| |doi=10.1016/0370-1573(77)90010-2
| |
| |pages=117–231
| |
| |year=1977
| |
| }}
| |
| | |
| ==External links==
| |
| *{{cite arXiv
| |
| |eprint=hep-ph/9608384
| |
| |title=Regge Pole Model for Vector Meson Photoproduction at HERA
| |
| |author1=Jenkovszky
| |
| |author2=Martynov
| |
| |author3=Paccanoni
| |
| |class=hep-ph
| |
| |year=1996
| |
| }}
| |
| *{{cite arXiv
| |
| |eprint=hep-ph/0103011
| |
| |title=Regge Poles in QCD
| |
| |author1=Kaidalov
| |
| |class=hep-ph
| |
| |year=2001
| |
| }}
| |
| *{{cite journal
| |
| |title=A universal Regge pole model for all vector meson exclusive photoproduction by real and virtual photons
| |
| |author1=Martynov
| |
| |author2=Predazzi
| |
| |author3=Prokudin
| |
| |year=2001
| |
| |doi=10.1140/epjc/s2002-01058-5
| |
| |journal=The European Physical Journal C
| |
| |volume=26
| |
| |issue=2
| |
| |pages=271–284
| |
| |arxiv=hep-ph/0112242
| |
| |bibcode = 2002EPJC...26..271M }}
| |
| *{{cite journal
| |
| |title=Quantized tension: Stringy amplitudes with Regge poles and parton behavior
| |
| |author1=Oleg Andreev
| |
| |author2=Warren Siegel
| |
| |year=2004
| |
| |doi=10.1103/PhysRevD.71.086001
| |
| |journal=Physical Review D
| |
| |volume=71
| |
| |issue=8
| |
| |arxiv=hep-th/0410131
| |
| |bibcode = 2005PhRvD..71h6001A }}
| |
| *{{cite journal
| |
| |title=Wilson Loop, Regge Trajectory and Hadron Masses in a Yang-Mills Theory from Semiclassical Strings
| |
| |author1=Bigazzi
| |
| |author2=Cotrone
| |
| |author3=Martucci
| |
| |author4=Pando Zayas
| |
| |year=2004
| |
| |doi=10.1103/PhysRevD.71.066002
| |
| |journal=Physical Review D
| |
| |volume=71
| |
| |issue=6
| |
| |arxiv=hep-th/0409205
| |
| |bibcode = 2005PhRvD..71f6002B }}
| |
| | |
| {{DEFAULTSORT:Regge Theory}}
| |
| [[Category:Particle physics]]
| |
| [[Category:Quantum chromodynamics]]
| |
They call me Emilia. South Dakota is her beginning place but she needs to move because of her family members. What I adore doing is playing baseball but I haven't produced a dime with it. Supervising is my occupation.
my weblog weight loss food delivery