Author : E. W. C. van Groesen
Publisher :
Page : 25 pages
File Size : 48,58 MB
Release : 1984
Category : Mathematics
ISBN :
Periodic solutions are investigated of the set of second order Hamiltonian equations -x = V'(x) for x(t) e R sub N, where the function V is even, has a certain monotonic behaviour on rays through the origin in R sub N and has superquadratic growth at infinity. It is proven that for T> 0 less than the smallest period of the linearized system (if non-trivial, else for all T), there exists a periodic solution of a special kind, a normal mode, which has minimal period T, has large amplitude (tending to infinity as T approaches limit of 0) and which minimizes the action functional on a naturally constrained set. If V has a direction of maximum increase this solution will be characterized completed. A condition for V is given, which is the same as in a multiplicity result for the prescribed energy case, that provides the existence of at least N distinct normal modes of minimal period T. (Author).