Singularities of inner functions associated with hyperbolic maps

Let $f$ be a function in the Eremenko-Lyubich class $\mathscr{B}$, and let $U$ be an unbounded, forward invariant Fatou component of $f$. We relate the number of singularities of an inner function associated to $\left.f\right|_{U}$ with the number of tracts of $f$. In particular, we show that if $f$...

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Detalhes bibliográficos
Autores: Evdoridou, Vasiliki, Fagella Rabionet, Núria, Jarque i Ribera, Xavier, Sixsmith, David J.
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2019
País:España
Recursos:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/164098
Acesso em linha:https://hdl.handle.net/2445/164098
Access Level:acceso abierto
Palavra-chave:Funcions de variables complexes
Funcions meromorfes
Sistemes dinàmics complexos
Functions of complex variables
Meromorphic functions
Complex dynamical systems
Descrição
Resumo:Let $f$ be a function in the Eremenko-Lyubich class $\mathscr{B}$, and let $U$ be an unbounded, forward invariant Fatou component of $f$. We relate the number of singularities of an inner function associated to $\left.f\right|_{U}$ with the number of tracts of $f$. In particular, we show that if $f$ lies in either of two large classes of functions in $\mathscr{B}$, and also has finitely many tracts, then the number of singularities of an associated inner function is at most equal to the number of tracts of $f$. Our results imply that for hyperbolic functions of finite order there is an upper bound -related to the order- on the number of singularities of an associated inner function.