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arXiv:2011.02902 · Journal of High Energy Physics

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

Song He, Yuan Sun, Yu-Xuan Zhang

Published Sep 1, 2021• 23 citations
arXivHTMLPDF

Abstract

Abstract In this paper, we investigate the partition functions of conformal field theories (CFTs) with the T $$ \overline{T} $$ 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.

DOI
10.1007/jhep09(2021)061

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