On the Three “Essential” Critical Values Theorem

  • Berardino Sciunzi

    Università della Calabria, Arcavacata di Rende, Italy


Global methods of the calculus of variations and the infinite dimensional critical point theory of Ljusternik and Schnirelmann are applied to give results on the existence of so-called critical values and essential critical values. The case of continuous, not necessarily differentiable functionals is considered and studied introducing a suitable variant of the Palais-Smale condition.

Cite this article

Berardino Sciunzi, On the Three “Essential” Critical Values Theorem. Z. Anal. Anwend. 20 (2001), no. 3, pp. 553–563

DOI 10.4171/ZAA/1030