Symmetric Orbifolds and Entanglement Entropy for Primary Excitations in Two Dimensional CFT

TL;DR

This paper computes the entanglement entropy for excited states in 2D CFTs using symmetric orbifold techniques, focusing on primary excitations and their correlation functions.

Contribution

It introduces a method to calculate entanglement entropy for primary excited states in 2D CFTs via symmetric orbifolding and n-point functions.

Findings

Derived a formula for entanglement entropy in excited states

Connected entanglement entropy to n-point functions of primary operators

Provided a framework for analyzing entanglement in orbifolded CFTs

Abstract

We use the techniques in symmetric orbifolding to calculate the Entanglement Entropy of a single interval in a two dimensional conformal field theory on a circle which is excited to a pure highest weight state. This is achieved by calculating the Reney Entropy which is found in terms of a 2n-point function of primary operators, n being the replica number.