Traveling waves for unbalanced bistable equation with density dependent diffusion

Abstract

We study the existence and qualitative properties of traveling wave solutions for the unbalanced bistable reaction-diffusion equation with a rather general density dependent diffusion coeffcient. In particular, it allows for singularities and/or degenerations as well as discontinuities of the fi rst kind at a fi nite number of points. The reaction term vanishes at equilibria and it is a continuous, possibly non-Lipschitz function. We prove the existence of a unique speed of propagation and a unique traveling wave pro le (up to translation) which is a non-smooth function in general. In the case of the power-type behavior of the diffusion and reaction near equilibria we provide detailed asymptotic analysis of the pro le.