Three-dimensional Bondi-Metzner-Sachs invariant two-dimensional field theories as the flat limit of Liouville theory

TL;DR

This paper constructs a new two-dimensional field theory invariant under BMS_3 symmetry by taking a flat limit of Liouville theory, aiming to describe boundary dynamics in 3D asymptotically flat gravity.

Contribution

It introduces a novel BMS_3 invariant 2D field theory as the flat limit of Liouville theory, linking conformal and BMS symmetries in gravitational contexts.

Findings

Derived a BMS_3 invariant field theory from Liouville theory.

Analyzed the boundary dynamics of flat 3D gravity.

Established a connection between conformal and BMS symmetries.

Abstract

In the gravitational context, Liouville theory is the two-dimensional conformal field theory that controls the boundary dynamics of asymptotically AdS_3 spacetimes at the classical level. By taking a suitable limit of the coupling constants of the Hamiltonian formulation of Liouville, we construct and analyze a BMS_3 invariant two-dimensional field theory that is likely to control the boundary dynamics at null infinity of three dimensional asymptotically flat gravity.