On the second order regularity of solutions to the parabolic $p$-Laplace equation

Abstract

In this paper, we study the second order Sobolev regularity of solutions to the parabolic $p$-Laplace equation. For any $p$-parabolic function $u$, we show that $D(|Du{|}^{\frac{p-2+s}{2}}Du)$ exists as a function and belongs to $L_{\text{loc}}^2$ with $s>-1$ and $1<p<\infty$. The range of $s$ is sharp.