Shi-type and Hamilton-type gradient estimates for a general parabolic equation under compact Finsler $CD(-K,N)$ geometric flows

TL;DR

This paper extends gradient estimate techniques to a broad class of parabolic equations on Finsler manifolds under geometric flows, removing previous restrictive curvature derivative bounds.

Contribution

It introduces Shi-type and Hamilton-type gradient estimates for parabolic equations on Finsler manifolds, relaxing curvature derivative conditions required in earlier studies.

Findings

Established gradient estimates under less restrictive curvature conditions.

Demonstrated the applicability of estimates to general parabolic equations.

Extended techniques from Riemannian to Finsler geometry.

Abstract

Recently, the Li-Yau-type gradient estimates for positive solutions to parabolic equations \begin{equation} \partial_t u=\Delta u+\mathcal{R}_1u+\mathcal{R}_2u^{\alpha}+\mathcal{R}_3u(\log u)^{\beta},\notag \end{equation} under the general compact Finsler $CD(-K,N)$ geometric flow are studied. Here $\mathcal{R}_1$,$\mathcal{R}_2$,$\mathcal{R}_3$ $\in$ $ C^{1}(M,[0,T])$, $\alpha$ and $\beta$ are both positive constants, $T$ is the maximal existence time for the flow. However, compared with the Riemannian case, the curvature conditions impose stricter derivative bounds on the development term in the geometric flow, as well as on the derivative bounds of the distortion of the manifold. In this manuscript, we present Shi-type and Hamilton-type gradient estimates to demonstrate the possibility of removing such conditions.