Energy Reflection and Transmission at 2D Holographic Interfaces

TL;DR

This paper presents a gravitational calculation of energy reflection and transmission at 2D holographic interfaces, revealing how these coefficients depend on interface tension and conformal field theory bounds.

Contribution

It provides the first gravitational computation of energy flux coefficients at 2D holographic interfaces with thin-brane duals, connecting to conformal field theory bounds.

Findings

Reflection coefficient depends monotonically on interface tension.

Reflection coefficient obeys ANEC-derived lower bound.

BCFT limit recovered at infinite central charge ratio.

Abstract

Scattering from conformal interfaces in two dimensions is universal in that the flux of reflected and transmitted energy does not depend on the details of the initial state. In this letter, we present the first gravitational calculation of energy reflection and transmission coefficients for interfaces with thin-brane holographic duals. Our result for the reflection coefficient depends monotonically on the tension of the dual string anchored at the interface, and obeys the lower bound recently derived from the ANEC in conformal field theory. The B(oundary)CFT limit is recovered for infinite ratio of the central charges.