Entire function whose escaping set has only bounded path-components

You need to know: Set {\mathbb C} of complex numbers, absolute value |z| of z\in{\mathbb C}, limits, function f(z) in complex variable z, its derivative f'(z), polynomials, notation f^n(z) for f(f(...f(z)...)) where f is applied n times, bounded subsets of {\mathbb C}, path (or curve) connecting points x \in {\mathbb C} and y \in {\mathbb C}.

Background: A function f:{\mathbb C}\to {\mathbb C} is called entire if f'(z) exists for all z\in {\mathbb C}. An entire function f is called transcendental if it is not a polynomial. An escaping set of a transcendental entire function f is the set I(f)=\{z\in {\mathbb C} : \lim\limits_{n\to\infty}|f^n(z)|=\infty\}. A path-component of I(f) is the set of all y\in I(f) which can be connected by a path P \subset I(f) to any fixed x\in I(f).

The Theorem: On 24th April 2007, Günter Rottenfusser, Johannes Rückert, Lasse Rempe, and Dierk Schleicher submitted to arxiv a paper in which they proved the existence of a transcendental entire function f whose escaping set I(f) has only bounded path-components.

Short context: The study of limiting behaviour of sequence f^n(z) for transcendental entire function f goes back to 1926 paper of Fatou. This is an example of dynamical system. In 1989, Eremenko, formalising a question of Fatou, asked whether the escaping set I(f) of any transcendental entire function f has the property that every point z\in I(f) can be joined with \infty by a curve in I(f). The Theorem answers this question in negative.

Links: Free arxiv version of the original paper is here, journal version is here.

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