{ "id": "1807.07270", "version": "v1", "published": "2018-07-19T07:40:00.000Z", "updated": "2018-07-19T07:40:00.000Z", "title": "Singularities of inner functions associated with hyperbolic maps", "authors": [ "Vasiliki Evdoridou", "NĂºria Fagella", "Xavier Jarque", "David J. Sixsmith" ], "categories": [ "math.DS", "math.CV" ], "abstract": "Let $f$ be a function in the Eremenko-Lyubich class $\\mathcal{B}$, and let $U$ be an unbounded, forward invariant Fatou component of $f$. We relate the number of singularities of an inner function associated to $f|_U$ with the number of tracts of $f$. In particular, we show that if $f$ lies in either of two large classes of functions in $\\mathcal{B}$, 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.", "revisions": [ { "version": "v1", "updated": "2018-07-19T07:40:00.000Z" } ], "analyses": { "keywords": [ "hyperbolic maps", "singularities", "associated inner function", "forward invariant fatou component", "upper bound" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }