The $$ \mathrm{T}\overline{\mathrm{T}} $$ perturbation and its geometric interpretation
Riccardo Conti (Dipartimento di Fisica and Arnold-Regge Center, Università di Torino and INFN, Sezione di Torino, Via P. Giuria 1, Torino, I-10125, Italy); Stefano Negro (C.N. Yang Institute for Theoretical Physics, New York Stony Brook, Stony Brook, NY, 11794-3840, U.S.A.); Roberto Tateo (Dipartimento di Fisica and Arnold-Regge Center, Università di Torino and INFN, Sezione di Torino, Via P. Giuria 1, Torino, I-10125, Italy)
Starting from the recently-discovered $$ \mathrm{T}\overline{\mathrm{T}} $$ -perturbed Lagrangians, we prove that the deformed solutions to the classical EoMs for bosonic field theories are equivalent to the unperturbed ones but for a specific field-dependent local change of coordinates. This surprising geometric outcome is fully consistent with the identification of $$ \mathrm{T}\overline{\mathrm{T}} $$ -deformed 2D quantum field theories as topological JT gravity coupled to generic matter fields. Although our conclusion is valid for generic interacting potentials, it first emerged from a detailed study of the sine-Gordon model and in particular from the fact that solitonic pseudo-spherical surfaces embedded in ℝ3 are left invariant by the deformation. Analytic and numerical results concerning the perturbation of specific sine-Gordon soliton solutions are presented.