Approximation property: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Mark viking
→‎Definition: Added wl
en>K9re11
removed Category:Functional analysis using HotCat as there are more specific categories
 
Line 1: Line 1:
{{Use dmy dates|date=May 2013}}
Roberto is what's written over his birth certificate fortunately he never really treasured that name. South Carolina is your birth place. The [http://www.Guardian.co.uk/search?q=favourite+hobby favourite hobby] for him and as well , his kids is to assist you fish and he's been for a while doing it for a very long time. Auditing is how he supports his own family. Go in which to his website to hit upon out more: http://circuspartypanama.com<br><br>
{{Infobox scientist
| name             =
| image            = Fatou.jpeg
| image_size        =
| alt              = Pierre Fatou
| caption          =
| birth_date        = {{Birth date|1878|2|28|df=y}}
| birth_place      = [[Lorient]]
| death_date        = {{Death date and age|1929|8|10|1878|2|28|df=y}}
| death_place      = [[Pornichet]]
| resting_place            =
| resting_place_coordinates = <!-- {{Coord|LAT|LONG|type:landmark|display=inline,title}} -->
| residence        =
| citizenship      =
| nationality      = French
| fields            = Mathematics
| workplaces        =
| alma_mater        =
| doctoral_advisor  =
| academic_advisors =
| doctoral_students =
| notable_students  =
| known_for        = [[Fatou lemma]] <br> [[Fatou set]] <br> [[Fatou&ndash;Bieberbach domain]]
| author_abbrev_bot =
| author_abbrev_zoo =
| influences        =
| influenced        =
| awards            =
| signature        = <!--(filename only)-->
| signature_alt    =
| footnotes        =
| spouse            =
}}
'''Pierre Joseph Louis Fatou''' (28 February 1878 – 10 August 1929) was a French mathematician and [[astronomer]]. He is known for major contributions to several branches of [[mathematical analysis|analysis]]. The [[Fatou lemma]] and the [[Fatou set]] are named after him.


==Biography==
Review my site: clash of clans hack cydia ([http://circuspartypanama.com Full Record])
[[File:Pierre Fatou.jpg|thumb|Pierre Fatou]]
 
Fatou entered the [[École Normale Supérieure]] in Paris in 1898 to study mathematics and graduated in 1901 when he was appointed an observer (''stagiaire'') in the [[Paris Observatory]]. Fatou was promoted to assistant astronomer in 1904 and to astronomer (''astronome titulaire'') in 1928. He worked in this observatory until his death.
 
Fatou was awarded the [[Henri Becquerel|Becquerel]] prize in 1918; he was a knight of the [[Legion of Honour]] (1923).{{sfn|Audin|2009|p=138}} He was the president of the [[Société Mathématique de France|French mathematical society]] in 1927.<ref>{{cite web|url=http://smf.emath.fr/VieSociete/Instances/AnciensPresidents.html|publisher=French mathematical society|title=Anciens Présidents|language=French}}</ref>
 
He was in friendly relations with several contemporary French mathematicians, especially, [[Maurice René Fréchet]] and [[Paul Montel]].{{sfn|Audin|2009|p=132}}
 
== Mathematical work of Fatou ==
Fatou's work had very large influence on the development of [[Mathematical analysis|analysis]] in the 20th century.
 
Fatou's PhD thesis ''Séries trigonométriques et séries de Taylor'' {{harv|Fatou|1906}} was the first application of the [[Lebesgue integral]] to concrete problems of [[mathematical analysis|analysis]], mainly to the study of analytic and harmonic functions in the unit disc. In this work, Fatou studied for the first time the [[Poisson integral]] of an arbitrary [[measure (mathematics)|measure]] on the unit circle. This work of Fatou is influenced by [[Henri Lebesgue]] who invented his integral in 1901.
 
The famous [[Fatou theorem]], which says that a bounded [[analytic function]] in the unit disc has radial limits [[almost everywhere]] on the unit circle was published in 1906 {{harv|Fatou|1906}}. This theorem was at the origin of a large body of research in 20th-century mathematics under the name of ''bounded analytic functions''.<ref>{{cite book|first=John B.|last=Garnett|title=Bounded analytic functions|publisher=[[Academic Press]]|year=1981}}</ref> See also the Wikipedia article on functions of [[Bounded type (mathematics)|bounded type]].
 
A number of fundamental results on the [[analytic continuation]] of a Taylor series belong to Fatou.<ref>{{cite book|first=Ludwig|last=Bieberbach|title=Analytische Fortsetzung|publisher=[[Springer Verlag]]|place=Berlin|year=1955}}</ref>
 
[[Image:Fatou1906-II.jpg|thumb|Julia set of
<math>\tfrac12(z+z^2)</math> investigated by
Fatou in 1906. This picture is made with a modern computer.]]
[[Image:Julia set of the Fatou function.png|thumb|Julia set of
''z''+1+''e''<sup>-''z''</sup> investigated by Fatou in 1926.]]
[[Image:Julia set of a map in the sine family.png|thumb|Julia set
of a sine function studied by Fatou in 1926]]
 
In 1917&ndash;1920 Fatou created the area of mathematics which is called [[holomorphic dynamics]] {{harvs|last=Fatou|year=1919|year2=1920|year3=1920b}}. It deals with a global study of iteration of analytic functions. He was the first to introduce and study the set which is called now the [[Julia set]]. (The complement of this set is sometimes called the [[Fatou set]]).
Some of the basic results of holomorphic dynamics were also independently obtained
by [[Gaston Julia]] and Samuel Lattes in 1918.
Holomorphic dynamics experienced a strong revival since 1982 because of the new discoveries of [[Dennis Sullivan]], [[Adrian Douady]], [[John Hamal Hubbard|John Hubbard]] and others. Beautiful pictures illustrating this theory produced by modern computers stimulate great interest not only of mathematicians but also outside of the mathematical community.
In 1926 Fatou pioneered the study of dynamics of [[Transcendental function|transcendental]] [[entire function]]s, a subject which is
[[escaping set|intensively developing]] at this time (2012).
 
As a byproduct of his studies in holomorphic dynamcis, Fatou discovered what are now called [[Fatou–Bieberbach domain]]s. These are proper subregions of the complex space of dimension ''n'' that are biholomorphically equivalent to the whole space. (Such regions cannot exist for ''n=1''.)
 
Fatou did important work in [[celestial mechanics]]. He was the first to prove rigorously
<ref>{{cite journal|first=Iu. A.|last=Mitropolsky|title=Averaging method in non-linear mechanics|journal=Intl. J. Non-Lin. Mech.|year=1967|volume=2|pages=69–95|bibcode=1967IJNLM...2...69M|doi=10.1016/0020-7462(67)90020-0}}</ref>
a theorem on the averaging of a [[perturbation theory|perturbation]] produced by a periodic force of short period, conjectured by [[Karl Friedrich Gauss|Gauss]], {{harv|Fatou|1928}}. This work was continued by
[[Leonid Mandelstam]] and [[Nikolay Bogolyubov]] and his students and developed in a large area of modern applied mathematics.
Fatou's other research in celestial mechanics includes a study of the movement of a planet in a resisting medium.
 
==Selected publications==
* {{cite journal|last=Fatou|first=P.|title=Séries trigonométriques et séries de Taylor|journal=Acta Math|volume=30|year=1906|ref=harv|jfm=37.0283.01|doi=10.1007/BF02418579|pages=335}}
* {{cite journal|last=Fatou|first=P.|title=Sur les équations fonctionnelles, I|journal=Bulletin de la Société Mathématique de France|volume=47|year=1919|pages=161&ndash;271|jfm=47.0921.02|url= http://www.numdam.org/item?id=BSMF_1919__47__161_0|ref=harv}}; {{cite journal|last=Fatou|first=P.|title=Sur les équations fonctionnelles, II|journal=Bulletin de la Société Mathématique de France|volume=48|year=1920|pages=33&ndash;94|jfm=47.0921.02|url=http://www.numdam.org/item?id=BSMF_1920__48__33_0|ref=harv}}; {{cite journal|last=Fatou|first=P.|title=Sur les équations fonctionnelles, III|journal=Bulletin de la Société Mathématique de France|volume=48|year=1920b|pages=208&ndash;314|jfm=47.0921.02|url=http://www.numdam.org/item?id=BSMF_1920__48__208_1|ref=harv}}
* {{cite journal|last=Fatou|first=P.|year=1923|journal=Bull. Soc. Math. France|volume=51|ref=harv|title=Sur les fonctions holomorphes et bornées à l'intérieur d'un cercle|pages=191&ndash;202|url=http://www.numdam.org/item?id=BSMF_1923__51__191_1|jfm=49.0221.01}}
* {{cite journal|last=Fatou|first=P.|year=1926|volume=47|journal=Acta Math|pages=337–370|title=Sur l'itération des fonctions transcendantes entières|doi=10.1007/BF02559517|issue=4}}
* {{cite journal|last=Fatou|first=P.|year=1928|journal=Bull. Soc. Math. France|volume=56|ref=harv|title=Sur le mouvement d'un système soumis à des forces à courte période|pages=98&ndash;139|jfm=54.0834.01|url= http://www.numdam.org/item?id=BSMF_1928__56__98_0}}
 
==Notes==
<references />
 
==See also==
*[[Fatou's theorem]]
*[[Fatou set]]
*[[Fatou–Lebesgue theorem]] (same as [[Fatou's lemma]])
*[[Classification of Fatou components]]
*[[Fatou&ndash;Bieberbach domain]]
*[[Holomorphic dynamics]]
 
==References==
* {{cite book|first=Michèle|last=Audin|year=2009|title=Fatou, Julia, Montel, le Grand prix des sciences mathématiques de 1918, et après...|url=http://www.springerlink.com/content/w0716l/#section=61104&page=1&locus=1|publisher=Springer|location=Heidelberg|isbn=978-3-642-00445-2|ref=harv}}
* {{cite paper|title=Notice sur les travaux scientifique de Pierre Fatou (pdf)|
url=http://www.math.purdue.edu/~eremenko/dvi/fatou-b.pdf|year=1929|place=Paris}}
* {{cite paper|first=Jean|last=Chazy|authorlink=Jean Chazy|title=Pierre Fatou|journal=Bulletin astronomique|year=1933|volume=8|pages=389&ndash;384}}
 
==External links==
* {{MacTutor Biography|id=Fatou}}
* [http://images.math.cnrs.fr/Pierre-Fatou-mathematicien-et.html Pierre Fatou, mathématicien et astronome] by Michèle Audin, on the site Images des Mathématiques.
* List of publications of Pierre Fatou on [http://www.emis.de/MATH/JFM/full.html Jahrbuch database].
* {{DSB|title=[http://www.encyclopedia.com/doc/1G2-2830901388.html Pierre Fatou]}}
* {{MathGenealogy|id=105160}}
* [http://www.ams.org/bookstore-getitem/item=HMATH-38 Early Days in Complex Dynamics: A History of Complex Dynamics in One Variable During 1906-1942] by Daniel S.Alexander, Felice Iavernaro, Alessandro Rosa
 
{{Authority control|VIAF=76398864}}
 
{{Persondata  <!-- Metadata: see [[Wikipedia:Persondata]].-->
| NAME              = Fatou, Pierre
| ALTERNATIVE NAMES =
| SHORT DESCRIPTION = French mathematician
| DATE OF BIRTH    = 28 February 1878
| PLACE OF BIRTH    = Lorient
| DATE OF DEATH    = 10 August 1929
| PLACE OF DEATH    = Pornichet
}}
{{DEFAULTSORT:Fatou, Pierre}}
[[Category:1878 births]]
[[Category:1929 deaths]]
[[Category:20th-century mathematicians]]
[[Category:French mathematicians]]
[[Category:École Normale Supérieure alumni]]

Latest revision as of 13:52, 11 January 2015

Roberto is what's written over his birth certificate fortunately he never really treasured that name. South Carolina is your birth place. The favourite hobby for him and as well , his kids is to assist you fish and he's been for a while doing it for a very long time. Auditing is how he supports his own family. Go in which to his website to hit upon out more: http://circuspartypanama.com

Review my site: clash of clans hack cydia (Full Record)