A critical point theorem related to the symmetric mountain pass lemma and its applications to elliptic equations

For an even functional on a Banach space, the symmetric mountain pass lemma gives a sequence of critical values which converges to zero. Under the same assumptions on the functional, this paper establishes a new critical point theorem which provides a sequence of critical points converging to zero. The theorem is applied to sublinear elliptic equations. Then a sequence of solutions converging to zero is obtained. (c) 2005 Elsevier Inc. All rights reserved.