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arXiv · 1003.2670

Gradient estimates for a nonlinear diffusion equation on complete manifolds

Jia-Yong Wu
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Abstract

Let $(M,g)$ be a complete non-compact Riemannian manifold with the $m$-dimensional Bakry-Émery Ricci curvature bounded below by a non-positive constant. In this paper, we give a localized Hamilton-type gradient estimate for the positive smooth bounded solutions to the following nonlinear diffusion equation \[ u_t=Δu-\nablaϕ\cdot\nabla u-au\log u-bu, \] where $ϕ$ is a $C^2$ function, and $a\neq0$ and $b$ are two real constants. This work generalizes the results of Souplet and Zhang (Bull. London Math. Soc., 38 (2006), pp. 1045-1053) and Wu (Preprint, 2008).

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BibTeXRIS

Jia-Yong Wu. 2010-03-13. Gradient estimates for a nonlinear diffusion equation on complete manifolds. https://doi.org/10.4208/jpde.v23.n1.4

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