Infinite entropy for transcendental entire functions

Defining entropy on noncompact metric spaces is a tricky business, since there are several natural and nonequivalent generalizations of the usual notions of entropy for continuous maps on compact spaces. By defining entropy for transcendental maps on the complex plane as the sup over the entropy restricted to compact forward invariant subsets, we prove that with this definition the entropy of such functions is infinite. The proof relies on covering results which are distinctive to holomorphic maps.