On equivalence of entropy and viscosity solutions to degenerate parabolic equations and applications
Hiroyoshi Mitake, Hiroshi Watanabe
TL;DR
This work establishes a precise equivalence between entropy solutions of anisotropic, degenerate parabolic-hyperbolic equations (CL) and viscosity solutions of degenerate quasilinear Hamilton-Jacobi equations (HJ), showing that, under a framework of structural assumptions, the derivative relation $u=\partial_x v$ pairs these two weak-solution notions. The main result proves two-way implications: from a Lipschitz viscosity solution $v$ of (HJ) one obtains the entropy solution $u=\partial_x v$ of (CL), and from an entropy solution $u$ of (CL) there exists a time-dependent additive function $\widehat{C}(t)$ such that $v(x,t)=\int_0^x u(y,t)\,dy + \widehat{C}(t)$ is a viscosity solution to (HJ). The paper also derives large-time behavior in the periodic setting, leveraging Panov-type results for (CL) and ergodic problem theory for (HJ), thereby describing the asymptotic profiles of solutions and their primitives. Overall, this work unifies entropy- and viscosity-based frameworks for a broad class of degenerate parabolic equations and provides concrete long-time asymptotics in periodic domains, enriching the theory and potential applications to nonlinear diffusion and Hamilton-Jacobi-type models.
Abstract
Here, we consider anisotropic degenerate parabolic-hyperbolic equations and degenerate quasilinear Hamilton-Jacobi equations. We prove the equivalence of two notions of entropy and viscosity solutions of two equations, and apply it to obtain a large-time behavior of viscosity solutions to quasilinear Hamilton-Jacobi equations, and entropy solutions to degenerate parabolic-hyperbolic equations in a periodic setting.
