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arXiv · 2109.10525

Perturbative renormalization of the $T \bar{T}$-deformed free massive Dirac fermion

Anshuman Dey·Aryeh Fortinsky
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Abstract

In this paper we explicitly carry out the perturbative renormalization of the $T\bar{T}$-deformed free massive Dirac fermion in two dimensions up to second order in the coupling constant. This is done by computing the two-to-two $S$-matrix using the LSZ reduction formula and canceling out the divergences by introducing counterterms. We demonstrate that the renormalized Lagrangian is unambiguously determined by demanding that it gives the correct $S$-matrix of a $T\bar{T}$-deformed integrable field theory. Remarkably, the renormalized Lagrangian is qualitatively very different from its classical counterpart.

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Anshuman Dey, Aryeh Fortinsky. 2021-09-22. Perturbative renormalization of the $T \bar{T}$-deformed free massive Dirac fermion. https://doi.org/10.1007/jhep12(2021)200

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