Global existence and nonexistence of semilinear wave equation with a new condition
Bolys Sabitbek
Abstract
In this paper, we consider the initial-boundary problem for semilinear wave equation with a new condition $$α\int_0^{u } f(s)ds \leq uf(u) + βu^2 +ασ,$$ for some positive constants $α$, $β$, and $σ$, where $β< \frac{λ_1(α-2)}{2}$ with $λ_1$ being a first eigenvalue of Laplacian. By introducing a family of potential wells, we establish the invariant sets, vacuum isolation of solutions, global existence and blow-up solutions of semilinear wave equation for initial conditions $E(0)<d$ and $E(0)=d$.
