Title: Quantum Dimension as Entanglement Entropy in 2D RCFTs

Speaker: Dr. Song He (Kyoto University)

Time: 10:00AM, Sep 23 (Wednesday)

Place: Theoretical Physics Division，319

Abstract: We study entanglement entropy of excited states in two dimensional conformal field theories (CFTs). Especially we consider excited states obtained by acting primary operators on a vacuum. We show that under its time evolution, entanglement entropy increases by a finite constant when the causality condition is satisfied. Moreover, in rational CFTs, we prove that this increased amount of (both Renyi and von-Neumann) entanglement entropy always coincides with the log of quantum dimension of the primary operator. Finally, we extend this study to BCFT and decendent excitation states in 2D RCFT.