Common fixed point theorems for nonexpansive mappings using the lower semicontinuity property

Abstract

Suppose that E is a Banach space, {\tau} a topology under which the norm of E becomes {\tau}-lower semicontinuous and S a commuting family of {\tau}-continuous nonexpansive mappings defined on a {\tau}-compact convex subset C of E: It is shown that the set of common fixed points of S is a nonempty nonexpansive retract of C. Along the way, a few other related fixed point theorems are derived.