ON A NEW MULTIPLE CRITICAL POINT THEOREM AND SOME APPLICATIONS TO ANISOTROPIC PROBLEMS

Abstract

Using the Fenchel-Young duality and mountain pass geometry we derive a new multiple critical point theorem. In a finite dimensional setting it becomes three critical point theorem while in an infinite dimensional case we obtain the existence of at least two critical points. The applications to anisotropic problems show that one can obtain easily that all critical points are nontrivial.