Hopf Bifurcation for General 1D Semilinear Wave Equations with Delay
arXiv:2011.06824 · doi:10.1007/s10884-021-10009-1
Abstract
We consider boundary value problems for 1D autonomous damped and delayed semilinear wave equations of the type with smooth coefficient functions and such that and for all and . We state conditions ensuring Hopf bifurcation, i.e., existence, local uniqueness (up to time shifts), regularity (with respect to and ) and smooth dependence (on and ) of small non-stationary time-periodic solutions, which bifurcate from the stationary solution , and we derive a formula which determines the bifurcation direction with respect to the bifurcation parameter . To this end, we transform the wave equation into a system of partial integral equations by means of integration along characteristics, and then we apply a Lyapunov-Schmidt procedure and a generalized implicit function theorem to this system. The main technical difficulties, which have to be managed, are typical for hyperbolic PDEs (with or without delay): small divisors and the "loss of derivatives" property. We do not use any properties of the corresponding initial-boundary value problem. In particular, our results are true also for negative delays .
36 pages