Existence and number of solutions to semilinear equations with applications to boundary-value problems

Abstract

solutions to nonlinear equations and to (non)resonant semilinear equations involving nonlinear perturbations of Fredholm maps of index zero. We apply our results to semilinear elliptic, and to semilinear parabolic and hyperbolic periodic boundary-value problems.

Keywords

• Existence
• number of solutions
• (pseudo) A-proper maps
• elliptic BVP's
• parabolic and hyperbolic equations.