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arXiv · 1006.4787

Curvature estimates for the level set of spatial quasiconcave solutions to a class of parabolic equations

Chuanqiang Chen·Shujun Shi
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Abstract

We prove a constant rank theorem for the second fundamental form of the spatial convex level surfaces of solutions to equations $u_t=F(\n^2u, \n u, u, t)$ under a structural condition, and give a geometric lower bound of the principal curvature of the spatial level surfaces.

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Chuanqiang Chen, Shujun Shi. 2010-06-24. Curvature estimates for the level set of spatial quasiconcave solutions to a class of parabolic equations. https://doi.org/10.1007/s11425-011-4277-7

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