Lorentz-symmetric solutions of nonlinear equations

Asymptotic properties of a real scalar self-interacting classical field depending on one variablez = t ²–x ² are studied. The field(z) approaches a minimum of the potentialU() for z + and a maximum forz– ifU((0)) is larger than two minima and smaller than two maxima ofU neighbouring to(0).Presented at the International Symposium Selected Topics in Quantum Field Theory and Mathematical Physics, Bechyn, Czechoslovakia, June 14–19, 1981.