Escaping points of commuting meromorphic functions with finitely many poles

Ferreira, Gustavo

doi:10.1090/proc/15591

Escaping points of commuting meromorphic functions with finitely many poles
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by Gustavo R. Ferreira PDF

Proc. Amer. Math. Soc. 150 (2022), 589-603 Request permission

Abstract:

Let $f$ and $g$ be commuting meromorphic functions with finitely many poles. By studying the behaviour of Fatou components under this commuting relation, we prove that $f$ and $g$ have the same Julia set whenever $f$ and $g$ have no simply connected fast escaping wandering domains. By combining this with a recent result of Tsantaris, we obtain the strongest statement (to date) regarding the Julia sets of commuting meromorphic functions. In order to highlight the difference to the entire case, we show that transcendental meromorphic functions with finitely many poles have orbits that alternate between approaching a pole and escaping to infinity at strikingly fast rates.

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