Asymptotically flat spacetimes in three-dimensional higher spin gravity

TL;DR

This paper establishes a set of asymptotic conditions for three-dimensional higher spin gravity with zero cosmological constant, revealing an extended BMS3 symmetry algebra and connecting to AdS3 results through gauge choices.

Contribution

It introduces a consistent framework for asymptotic conditions in 3D higher spin gravity with flat spacetime and identifies the associated extended symmetry algebra.

Findings

Asymptotic symmetry algebra is a higher spin extension of BMS3.

Results connect flat and AdS3 spacetimes via gauge transformations.

Provides a foundation for studying flat space holography in higher spin theories.

Abstract

A consistent set of asymptotic conditions for higher spin gravity in three dimensions is proposed in the case of vanishing cosmological constant. The asymptotic symmetries are found to be spanned by a higher spin extension of the BMS3 algebra with an appropriate central extension. It is also shown that our results can be recovered from the ones recently found for asymptotically AdS3 spacetimes by virtue of a suitable gauge choice that allows to perform the vanishing cosmological constant limit.