Non-Wilsonian RG flows and the $\mathrm{T}\bar{\mathrm{T}}$ perturbation of $2$D QFT

Stefano Negro

ENS

Wed, Dec. 14th 2016, 14:30

Pièce 35, Bât. 774, Orme des Merisiers

\noindent ``Integrability meeting ENS/IPhT'' \\ \par Since many year it is known that the confining flux tube between a quark and an anti-quark in $D$ dimensions can be very efficiently described by the Conformal Field Theory of $D-2$ massless free bosons. The deviation from this theory are then well approximated by Nambu-Goto string action. Recently it was observed that these deviation can be realised, in the $S$-matrix framework, as the deformation of the free boson scattering matrix by a CDD factor. After a brief review of the effective string theory for confining quark-anti-quark flux tube, I will show how the presence of a non-trivial CDD factor can be interpreted as a deformation of the CFT action by an irrelevant operator constructed from the energy-momentum tensor components. This deformation enjoys peculiar properties and allows for an exact determination of the spectrum. I will present the properties of this deformation and show how it can be extended to a generic, not necessarily integrable, QFT. \\ \\ (Organizer: IPhT/Ivan Kostov)

Contact : lbervas