Black holes and universality classes of critical points

TL;DR

This paper discusses a universal ratio of central charge to entropy density in a broad class of conformal field theories, which can indicate the presence of a classical gravity dual via AdS/CFT correspondence.

Contribution

It introduces a universal ratio c/c' for conformal field theories with gravity duals, providing a practical test for duality applicability.

Findings

Universal ratio c/c' exists for theories with gravity duals.

The ratio serves as a criterion to identify theories with classical gravity descriptions.

The class includes diverse conformal theories across dimensions.

Abstract

We argue that there exists an infinite class of conformal field theories in diverse dimensions, having a universal ratio of the central charge c to the normalized entropy density c'. The universality class includes all conformal theories which possess a classical gravity dual according to the AdS/CFT correspondence. From the practical point of view, the universality of c/c' provides an explicit test which can be applied to determine whether a given critical point may admit a dual description in terms of classical gravity.