On convergence to the Denjoy-Wolff point

被引:20
作者
Bourdon, PS [1 ]
Matache, V
Shapiro, JH
机构
[1] Washington & Lee Univ, Dept Math, Lexington, VA 24450 USA
[2] Univ Nebraska, Dept Math, Omaha, NE 68182 USA
[3] Michigan State Univ, E Lansing, MI 48824 USA
关键词
D O I
10.1215/ijm/1258138025
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
For holomorphic selfmaps of the open unit disc U that are not elliptic automorphisms, the Schwarz Lemma and the Denjoy-Wolff Theorem combine to yield a remarkable result: each such map W has a (necessarily unique) "Denjoy-Wolff point" omega in the closed unit disc that attracts every orbit in the sense that the iterate sequence (phi([n])) converges to w uniformly on compact subsets of U. In this paper we prove that, except for the obvious counterexamples-inner functions having omega is an element of U-the iterate sequence exhibits an even stronger affinity for the Denjoy-Wolff point; phi([n]) -> to in the norm of the Hardy space HP for 1 <= p < infinity. For each such map, some subsequence of iterates converges to w almost everywhere on partial derivative U, and this leads us to investigate the question of almost-everywhere convergence of the entire iterate sequence. Here our work makes natural connections with two important aspects of the study of holomorphic selfmaps of the unit disc: linear- fractional models and ergodic properties of inner functions.
引用
收藏
页码:405 / 430
页数:26
相关论文
共 29 条
[1]  
AARONSON J, 1981, J LOND MATH SOC, V23, P469
[2]  
AARONSON J, 1978, ANN I H POINCARE B, V14, P233
[3]  
Aaronson J., 1997, Math. Surveys and Monographs, V50
[4]  
[Anonymous], 1884, ANN SCI COLE NORM SU
[5]  
Axler S., 2001, GRAD TEXT M, V137, DOI 10.1007/978-1-4757-8137-3
[6]  
BAKER IN, 1979, J LOND MATH SOC, V20, P255
[7]  
Bourdon PS, 1997, MEM AM MATH SOC, V125, P1
[8]   Identity principles for commuting holomorphic self-maps of the unit disc [J].
Bracci, F ;
Tauraso, R ;
Vlacci, F .
JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS, 2002, 270 (02) :451-473
[9]  
Burns D. M., 1994, J AM MATH SOC, V7, P661, DOI [10.1090/S0894-0347-1994-1242454-2, DOI 10.1090/S0894-0347-1994-1242454-2]
[10]  
Cowen C., 1995, COMPOSITION OPERATOR