Holographic two-point functions for Janus interfaces in the $D1/D5$ CFT

TL;DR

This paper computes explicit two-point functions for scalar operators in a top-down holographic Janus interface setup within the D1/D5 CFT, providing new analytic solutions and insights into defect conformal field theories.

Contribution

It presents the first analytic two-point function calculation for a fully-backreacted, top-down holographic defect in the D1/D5 CFT, including explicit bulk-to-bulk propagator and conformal block expansion.

Findings

Derived explicit bulk-to-bulk propagator.

Obtained two-point correlation functions involving defect operators.

Discussed potential finite-temperature extensions.

Abstract

This paper investigates scalar perturbations in the top-down supersymmetric Janus solutions dual to conformal interfaces in the $D1/D5$ CFT, finding analytic closed-form solutions. We obtain an explicit representation of the bulk-to-bulk propagator and extract the two-point correlation function of the dual operator with itself, whose form is not fixed by symmetry alone. We give an expression involving the sum of conformal blocks associated with the bulk-defect operator product expansion and briefly discuss finite-temperature extensions. To our knowledge, this is the first two-point function computation for a fully-backreacted, top-down holographic defect.