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arXiv · 2308.04174

The parametrix construction of the heat kernel on a graph

Gautam Chinta·Jay Jorgenson·Anders Karlsson·Lejla Smajlović
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Abstract

In this paper we develop the parametrix approach for constructing the heat kernel on a graph $G$. In particular, we highlight two specific cases. First, we consider the case when $G$ is embedded in a Eulidean domain or manifold $\Omega$, and we use a heat kernel associated to $\Omega$ to obtain a formula for the heat kernel on $G$. Second, we consider when $G$ is a subgraph of a larger graph $\widetilde{G}$, and we obtain a formula for the heat kernel on $G$ from the heat kernel on $\widetilde{G}$ restricted to $G$.

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Gautam Chinta, Jay Jorgenson, Anders Karlsson, Lejla Smajlović. 2023-08-08. The parametrix construction of the heat kernel on a graph. https://arxiv.org/abs/2308.04174

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