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arXiv · 2112.00074

The Brownian loop soup stress-energy tensor

Federico Camia·Valentino F. Foit·Alberto Gandolfi·Matthew Kleban
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Abstract

The Brownian loop soup (BLS) is a conformally invariant statistical ensemble of random loops in two dimensions characterized by an intensity $\lambda>0$. Recently, we constructed families of operators in the BLS and showed that they transform as conformal primary operators. In this paper we provide an explicit expression for the BLS stress-energy tensor and compute its operator product expansion with other operators. Our results are consistent with the conformal Ward identities and our previous result that the central charge is $c = 2 \lambda$. In the case of domains with boundary we identify a boundary operator that has properties consistent with the boundary stress-energy tensor. We show that this operator generates local deformations of the boundary and that it is related to a boundary operator that induces a Brownian excursion starting or ending at its insertion point.

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Federico Camia, Valentino F. Foit, Alberto Gandolfi, Matthew Kleban. 2021-11-30. The Brownian loop soup stress-energy tensor. https://doi.org/10.1007/jhep11(2022)009

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