The hyperbolic region for hyperbolic boundary value problems (Q661393)

The author studies the initial-boundary-value problem for linear first order hyperbolic systems in \(\mathbb{R}^d\) half-space with Dirichlet boundary conditions. In order to determine whether the problem is weakly well-posed, one must locate the hyperbolic region of the problem. The presented criterion ensures that the hyperbolic region coincides with the projection of the forward cone. Examples show that the criterion is sharp.