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arXiv · 1706.06249

On the Li-Yau type gradient estimate of Li and Xu

Zhigang Chen·Chengjie Yu·Feifei Zhao
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Abstract

In this paper, we obtain a Li-Yau type gradient estimate with time dependent parameter for positive solutions of the heat equation, so that the Li-Yau type gradient estimate of Li-Xu are special cases of the estimate. We also obtain improvements of Davies' Li-Yau type gradient estimate. The argument is different with those of Li-Xu and Qian.

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Zhigang Chen, Chengjie Yu, Feifei Zhao. 2017-06-20. On the Li-Yau type gradient estimate of Li and Xu. https://arxiv.org/abs/1706.06249

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