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arXiv · 2011.02902

$T\bar{T}$-flow effects on torus partition functions

Song He·Yuan Sun·Yu-Xuan Zhang
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Abstract

In this paper, we investigate the partition functions of conformal field theories (CFTs) with the $T\bar{T}$ deformation on a torus in terms of the perturbative QFT approach. In Lagrangian path integral formalism, the first- and second-order deformations to the partition functions of 2D free bosons, free Dirac fermions, and free Majorana fermions on a torus are obtained. The corresponding Lagrangian counterterms in these theories are also discussed. The first two orders of the deformed partition functions and the first-order vacuum expectation value (VEV) of the first quantum KdV charge obtained by the perturbative QFT approach are consistent with results obtained by the Hamiltonian formalism in literature.

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Song He, Yuan Sun, Yu-Xuan Zhang. 2020-11-05. $T\bar{T}$-flow effects on torus partition functions. https://doi.org/10.1007/jhep09(2021)061

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