Conformal Janus on Euclidean Sphere

TL;DR

This paper investigates the properties of Janus interfaces in conformal field theories using AdS/CFT correspondence, computing interface free energy through gravity and conformal perturbation theory, confirming their agreement and conformal scaling.

Contribution

It provides a detailed analysis of Janus interfaces as conformal defects, demonstrating the consistency of free energy calculations from gravity and field theory perspectives.

Findings

Interface free energy computed from gravity matches conformal perturbation theory.

The free energy scales according to conformal invariance expectations.

The study confirms Janus as a well-defined conformal interface in CFTs.

Abstract

We interpret Janus as an interface in a conformal field theory and study its properties. The Janus is created by an exactly marginal operator and we study its effect on the interface conformal field theory on the Janus. We do this by utilizing the AdS/CFT correspondence. We compute the interface free energy both from leading correction to the Euclidean action in the dual gravity description and from conformal perturbation theory in the conformal field theory. We find that the two results agree each other and that the interface free energy scales precisely as expected from the conformal invariance of the Janus interface.