An Existence Theorem for Wave‐Type Hyperbolic Hemivariational Inequalities

In this paper we prove the existence of solutions for a hyperbolic hemivariationalinequality of the form u″ + Bu + ∂j (u) ∋ f where B is a linear elliptic operator and ∂j is the Clarke subdifferential of a locally Lipschitz function j. Our result is based on the parabolic regularization method.