翻訳と辞書
Words near each other
・ Fatou
・ Fatou Bensouda
・ Fatou Bintou Fall
・ Fatou conjecture
・ Fatou Coulibaly
・ Fatou Dieng
・ Fatou Diome
・ Fatou Jaw-Manneh
・ Fatou Keïta
・ Fatou N'Diaye
・ Fatou N'Diaye (basketball)
・ Fatou Ndiaye Sow
・ Fatou Niang Siga
・ Fatou Tiyana
・ Fatou's lemma
Fatou's theorem
・ Fatoumata Bagayoko
・ Fatoumata Dembélé Diarra
・ Fatoumata Diawara
・ Fatoumata Diop
・ Fatoumata Kaba
・ Fatoumata Koné
・ Fatoumata Nafo-Traoré
・ Fatoumata Samassékou
・ Fatouville-Grestain
・ Fatou–Bieberbach domain
・ Fatou–Lebesgue theorem
・ Fatoş Gürkan
・ Fatoş Yıldırım
・ Fatpaint


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Fatou's theorem : ウィキペディア英語版
Fatou's theorem

In complex analysis, Fatou's theorem, named after Pierre Fatou, is a statement concerning holomorphic functions on the unit disk and their pointwise extension to the boundary of the disk.
==Motivation and statement of theorem==

If we have a holomorphic function f defined on the open unit disk D^=\, it is reasonable to ask under what conditions we can extend this function to the boundary of the unit disk. To do this, we can look at what the function looks like on each circle inside the disk centered at 0, each with some radius r. This defines a new function on the circle f_:S^\rightarrow \mathbb, defined by f_(e^)=f(re^), where S^:=\=\. Then it would be expected that the values of the extension of f onto the circle should be the limit of these functions, and so the question reduces to determining when f_ converges, and in what sense, as r\rightarrow 1, and how well defined is this limit. In particular, if the L^p norms of these f_ are well behaved, we have an answer:
:Theorem: Let f:D^\rightarrow\mathbb be a holomorphic function such that
:: \sup_\lVert f_\rVert_)}<\infty.
Then f_ converges to some function f_\in L^(S^) pointwise almost everywhere and in L^. That is,
:: \lVert f_-f_\rVert_)}\rightarrow 0
:and
:: |f_(e^)-f_(e^)|\rightarrow 0
:for almost every \theta\in ().
Now, notice that this pointwise limit is a radial limit. That is, the limit being taken is along a straight line from the center of the disk to the boundary of the circle, and the statement above hence says that
: f(re^)\rightarrow f_(e^)
for almost every \theta. The natural question is, now with this boundary function defined, will we converge pointwise to this function by taking a limit in any other way? That is, suppose instead of following a straight line to the boundary, we follow an arbitrary curve \gamma:, \lim_f(\gamma(t))=f_(e^)
: for every nontangential limit \gamma converging to e^, where f_ is defined as above.

抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)
ウィキペディアで「Fatou's theorem」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.