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arXiv · 2110.09736

Schwarz symmetrizations in parabolic equations on complete manifolds

Haiqing Cheng·Tengfei Ma·Kui Wang
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Abstract

In this article, we prove a sharp estimate for the solutions to parabolic equations on manifolds. Precisely, using symmetrization techniques and isoperimetric inequalities on Riemannian manifold, we obtain a Bandle's comparison on complete noncompact manifolds with nonnegative Ricci curvature and compact manifolds with positive Ricci curvature respectively. Our results generalize Bandle's result [6] to Riemannian setting, and Talenti's comparison for elliptic equation on manifolds by Colladay-Langford-McDonald [12] and Chen-Li [9] to parabolic equations.

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Haiqing Cheng, Tengfei Ma, Kui Wang. 2021-10-19. Schwarz symmetrizations in parabolic equations on complete manifolds. https://arxiv.org/abs/2110.09736

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