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arXiv · 2012.08763

Uniform Complex Time Heat Kernel Estimates Without Gaussian Bounds

Shiliang Zhao·Quan Zheng
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Abstract

In this paper, first we consider the uniform complex time heat kernel estimates of $e^{-z(-\Delta)^{\frac{\alpha}{2}}}$ for $\alpha>0, z\in \mathbb{C}^+$. When $\frac{\alpha}{2}$ is not an integer, generally the heat kernel doest not have the Gaussian upper bounds for real time. Thus the Phragm\'en-Lindel\"of methods fail to give the uniform complex time estimates. Instead, our first result gives the asymptotic estimates for $P(z, x)$ as $z$ tending to the imaginary axis. Then we prove the uniform complex time heat kernel estimates. Finally we also show the uniform estimates of analytic semigroup generated by $H=(-\Delta)^{\frac{\alpha}{2}}+V$ where $V$ belongs to higher order Kato class.

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Shiliang Zhao, Quan Zheng. 2020-12-16. Uniform Complex Time Heat Kernel Estimates Without Gaussian Bounds. https://arxiv.org/abs/2012.08763

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