EQUIVALENTS TO EKELAND’S VARIATIONAL PRINCIPLE IN LOCALLY COMPLETE SPACES.

抄録

In this paper we prove an extension of Ekeland’s variational principle in the setting of locally complete spaces. We also present an Equilibrium version of the Ekeland-type variational principle, a Caristi-Kirk type fixed point theorem for multivalued maps and a Takahashi minimization theorem, we then prove that they are equivalent.