Constraints on symmetry from holography

TL;DR

Using holography, the paper confirms that quantum gravity prohibits global symmetries, requires gauge groups to be compact, and mandates dynamical objects for all representations, supporting longstanding conjectures about fundamental symmetries.

Contribution

The paper provides a holographic derivation of key conjectures about symmetries in quantum gravity, linking non-perturbative consistency to these fundamental constraints.

Findings

No global symmetries in quantum gravity

Gauge groups must be compact

Dynamical objects exist for all representations

Abstract

In this letter we use the Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence to establish a set of old conjectures about symmetries in quantum gravity. These are that no global symmetries are possible, that internal gauge symmetries must come with dynamical objects that transform in all irreducible representations, and that internal gauge groups must be compact. These conjectures are not obviously true from a bulk perspective, they are nontrivial consequences of the non-perturbative consistency of the correspondence. More details of and background for these arguments are presented in an accompanying paper.