This monograph presents in a unified manner the use of the Morse index, and especially its connections to the maximum principle, in the study of nonlinear elliptic equations. The knowledge or a bound on the Morse index of a solution is a very important qualitative information which can be used in several ways for different problems, in order to derive uniqueness, existence or nonexistence, symmetry, and other properties of solutions.

Autorentext

Lucio Damascelli, University of Rome Tor Vergatä, Italy; Filomena Pacella, University of Rome La Sapienzä, Italy