A flower structure of backward flow invariant domains for semigroups
arXiv:math/0511718
Abstract
In this paper, we study conditions which ensure the existence of backward flow invariant domains for semigroups of holomorphic self-mappings of a simply connected domain . More precisely, the problem is the following. Given a one-parameter semigroup on , find a simply connected subset such that each element of is an automorphism of , in other words, such that forms a one-parameter group on . On the way to solving this problem, we prove an angle distortion theorem for starlike and spirallike functions with respect to interior and boundary points.