TTbar deformation and the light-cone gauge

TL;DR

This paper links TTbar deformation in quantum field theory to gauge invariance in string theory's light-cone gauge, deriving deformed Lagrangians for various fields and clarifying the deformation's stress-energy tensor origin.

Contribution

It provides a novel interpretation of TTbar deformation as a gauge invariance condition in string theory and derives explicit deformed Lagrangians for multiple field types.

Findings

TTbar deformation corresponds to gauge invariance of target space-time energy and momentum.

Derived the TTbar deformed Lagrangian for scalars, fermions, and chiral bosons.

Found the deformation is driven by the canonical Noether stress-energy tensor.

Abstract

The homogeneous inviscid Burgers equation which determines the spectrum of a TTbar deformed model has a natural interpretation as the condition of the gauge invariance of the target space-time energy and momentum of a (non-critical) string theory quantised in a generalised uniform light-cone gauge which depends on the deformation parameter. As a simple application of the light-cone gauge interpretation we derive the TTbar deformed Lagrangian for a system of any number of scalars, fermions and chiral bosons with an arbitrary potential. We find that the TTbar deformation is driven by the canonical Noether stress-energy tensor but not the covariant one.