Fixed point theorems for condensing admissible maps in topological vector spaces

Abstract

Introducing the notion of c-measure of noncompactness due to S. Hahn, we give a homotopy extension theorem and the fixed point property for pseudo-condensing admissible maps in general topological vector spaces. Moreover, these results are applied to obtain a Leray-Schauder type fixed point theorem for pseudo-condensing admissible maps in topological vector spaces which includes many known results.