ANTIPERIODIC SOLUTIONS TO A CLASS OF NONLINEAR DIFFERENTIAL-EQUATIONS IN HILBERT-SPACE

A broad class of nonlinear, non-monotone anti-periodic boundary value problems in a Hilbert space is considered. As a preliminary step, the existence, uniqueness and continuous dependence upon data of anti-periodic solutions to some first- and second-order evolution equations associated to odd, noncoercive monotone operators is established. Applications of the theory to nonlinear partial differential equations are also discussed. © 1991.