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arXiv · 2502.07210

Generalized Harnack Inequality for Mean Curvature Flow and Ancient Solutions

Junyoung Park
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Abstract

The goal of this paper is to relax convexity assumption on some classical results in mean curvature flow. In the first half of the paper, we prove a generalized version of Hamilton's differential Harnack inequality which holds for mean convex solutions to mean curvature flow with a lower bound on $\frac{\lambda_1}{H}$ where $\lambda_1$ is the smallest principal curvature. Then, we use classical maximum principle to provide several characterizations of family of shrinking spheres for closed, mean convex ancient solution to mean curvature flow with a lower bound on $\frac{\lambda_1 + .. + \lambda_k}{H}$ for some $1 \leq k \leq d-1$, where $\lambda_1 \leq \lambda_2 \leq .. \leq \lambda_d$ are the principal curvatures.

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Junyoung Park. 2025-02-11. Generalized Harnack Inequality for Mean Curvature Flow and Ancient Solutions. https://arxiv.org/abs/2502.07210

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