TY - BOOK AU - Bartsch,Thomas ED - SpringerLink (Online service) TI - Topological Methods for Variational Problems with Symmetries T2 - Lecture Notes in Mathematics, SN - 9783540480990 AV - QA612-612.8 U1 - 514.2 23 PY - 1993/// CY - Berlin, Heidelberg PB - Springer Berlin Heidelberg KW - Mathematics KW - Global analysis (Mathematics) KW - Algebraic topology KW - Cell aggregation KW - Algebraic Topology KW - Analysis KW - Manifolds and Cell Complexes (incl. Diff.Topology) N1 - Category, genus and critical point theory with symmetries -- Category and genus of infinite-dimensional representation spheres -- The length of G-spaces -- The length of representation spheres -- The length and Conley index theory -- The exit-length -- Bifurcation for O(3)-equivariant problems -- Multiple periodic solutions near equilibria of symmetric Hamiltonian systems N2 - Symmetry has a strong impact on the number and shape of solutions to variational problems. This has been observed, for instance, in the search for periodic solutions of Hamiltonian systems or of the nonlinear wave equation; when one is interested in elliptic equations on symmetric domains or in the corresponding semiflows; and when one is looking for "special" solutions of these problems. This book is concerned with Lusternik-Schnirelmann theory and Morse-Conley theory for group invariant functionals. These topological methods are developed in detail with new calculations of the equivariant Lusternik-Schnirelmann category and versions of the Borsuk-Ulam theorem for very general classes of symmetry groups. The Morse-Conley theory is applied to bifurcation problems, in particular to the bifurcation of steady states and hetero-clinic orbits of O(3)-symmetric flows; and to the existence of periodic solutions nearequilibria of symmetric Hamiltonian systems. Some familiarity with the usualminimax theory and basic algebraic topology is assumed UR - http://dx.doi.org/10.1007/BFb0073859 ER -