Equilibrium existence theorems in KKM spaces

Abstract

An abstract convex space satisfying the KKM principle is called a KKM space. This class of spaces contains G -convex spaces properly. In this work, we show that a large number of results in KKM theory on G -convex spaces also hold on KKM spaces. Examples of such results are theorems of Sperner and Alexandroff–Pasynkoff, Fan–Browder type fixed point theorems, Horvath type fixed point theorems, Ky Fan type minimax inequalities, variational inequalities, von Neumann type minimax theorems, Nash type equilibrium theorems, and Himmelberg type fixed point theorems.