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arXiv · 1806.03637

An asymptotic expansion of the trace of the heat kernel of a singular two-particle contact interaction in one dimension

Sebastian Egger
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Abstract

The regularized trace of the heat kernel of a one-dimensional Schr\"odinger operator with a singular two-particle contact interaction being of Lieb-Liniger type is considered. We derive a complete small-time asymptotic expansion in (fractional) powers of the time, $t$. Most importantly, we do not invoke standard parametrix constructions for the heat kernel. Instead, we first derive the large-energy expansion of the regularized trace of the resolvent for the considered operator. Then, we exploit that the resolvent may be obtained by a Laplace transformation of the heat semi-group, and an application of a suitable inverse Watson lemma eventually yields the small-$t$ asymptotic expansion of the heat-kernel trace.

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Sebastian Egger. 2018-06-10. An asymptotic expansion of the trace of the heat kernel of a singular two-particle contact interaction in one dimension. https://arxiv.org/abs/1806.03637

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