On differences of self-adjoint semigroups
De tels problèmes mixtes sont étudiés dans certains domaines non cylindriques, lorsque les conditions à l’instant initial sont celles de Cauchy, par l’intermédiaire de problèmes pseudo-différentiels sur le bord latéral du domaine. On donne des conditions qui permettent d’établir l’existence ou l’unicité de la solution.
Large time behavior of solutions to the generalized damped wave equation for is studied. First, we consider the linear nonhomogeneous equation, i.e. with F = F(x,t) independent of u. We impose conditions on the operators A and B, on F, as well as on the initial data which lead to the selfsimilar large time asymptotics of solutions. Next, this abstract result is applied to the equation where , , and the nonlinear term is either or . In this case, the asymptotic profile of solutions is given...