Topological Methods for Variational Problems with Symmetries

Symmetry has a strong impact on the number and shape ofsolutions to variational problems. This has been observed,for instance, in the search for periodic solutions ofHamiltonian systems or of the nonlinear wave equation; whenone is interested in elliptic equations on symmetric domainsor in the corresponding semiflows; and when one is lookingfor "special" solutions of these p...