Continuity of separately continuous mappings

Abstract

Abstract By means of a topological game, a class of topological spaces which contains compact spaces, q-spaces and W-spaces was defined in [BOUZIAD, A.: The Ellis theorem and continuity in groups, Topology Appl. 50 (1993), 73–80]. We will show that if Y belongs to this class, every separately continuous function f: X × Y → Z is jointly continuous on a dense subset of X × Y provided that X is σ-β-unfavorable and Z is a regular weakly developable space.