Continuity estimates for degenerate parabolic double-phase equations via nonlinear potentials
Qifan Li
TL;DR
The paper develops a regularity theory for bounded weak solutions of degenerate parabolic double-phase equations by linking nonlinear potential theory to a De Giorgi–Kilpeläinen–Malý framework in intrinsic cylinders. It proves local continuity with explicit oscillation decay in terms of elliptic Riesz potentials $F_p$ and $G_p$, under nonlinear Kato-type conditions $f\in K_p$ and $g\in \tilde K_p$, and structural assumptions on the coefficient $a(x,t)$. The method combines Caccioppoli inequalities, logarithmic estimates, and two complementary De Giorgi alternatives (first and second) to derive decay of oscillation across shrinking intrinsic cylinders, yielding Hölder-type continuity and quantitative bounds. The results extend to the parabolic $p$- and $(p,q)$-phase settings and provide a potential-theoretic characterization of regularity via $F_p$ and $G_p$, with uniform estimates in the $p$-phase and refined bounds when $a_0>0$, offering a robust regularity framework for parabolic double-phase problems.
Abstract
In this article, we study regularity properties for degenerate parabolic double-phase equations. We establish continuity estimates for bounded weak solutions in terms of elliptic Riesz potentials on the right-hand side of the equation.
