Gradient estimates for a simple nonlinear heat equation on manifolds

Li Ma

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arXiv · 1009.0604

Gradient estimates for a simple nonlinear heat equation on manifolds

Li Ma

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Abstract

In this paper, we study the gradient estimate for positive solutions to the following nonlinear heat equation problem $$ u_t-Δu=au\log u+Vu, \ \ u>0 $$ on the compact Riemannian manifold $(M,g)$ of dimension $n$ and with non-negative Ricci curvature. Here $a\leq 0$ is a constant, $V$ is a smooth function on $M$ with $-ΔV\leq A$ for some positive constant $A$. This heat equation is a basic evolution equation and it can be considered as the negative gradient heat flow to $W$-functional (introduced by G.Perelman), which is the Log-Sobolev inequalities on the Riemannian manifold and $V$ corresponds to the scalar curvature.

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BibTeX RIS

Li Ma. 2010-09-03. Gradient estimates for a simple nonlinear heat equation on manifolds. https://arxiv.org/abs/1009.0604

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