Warped Conformal Field Theory

TL;DR

This paper introduces warped conformal field theories with chiral scaling symmetry, deriving a universal density of states formula, and applies it to holographic black hole entropy in warped AdS_3 and string theory.

Contribution

It develops the theory of warped conformal field theories with specific symmetries and demonstrates their application to black hole entropy calculations.

Findings

Universal formula for asymptotic density of states derived.

Matching of field theory density of states with black hole entropy.

Symmetries lead to modular covariance of the partition function.

Abstract

We study field theories in two spacetime dimensions invariant under a chiral scaling symmetry that acts only on right-movers. The local symmetries include one copy of the Virasoro algebra and a U(1) current algebra. This differs from the 2d conformal group, but in some respects is equally powerful in constraining the theory. In particular, the symmetries on a torus lead to modular covariance of the partition function, which is used to derive a universal formula for the asymptotic density of states. For an application we turn to the holographic description of black holes in quantum gravity, motivated by the fact that the symmetries in the near horizon geometry of any extremal black hole are identical to those of a 2d field theory with chiral scaling. We consider two examples: black holes in warped AdS_3 in topologically massive gravity, and in string theory. In both cases, the density of states in the 2d field theory reproduces the Bekenstein-Hawking entropy of black holes in the gravity theory.