Speaker
Dr
Benjamin Doyon
(King's College London)
Description
In this talk I will show that the entanglement entropy of a region of large size ℓ in a one-dimensional non-unitary critical model behaves as S∼(ceff/3)logℓ, where ceff=c−24Δ>0 is the effective central charge, c (which may be negative) is the central charge of the conformal field theory and Δ≤0 is the lowest holomorphic conformal dimension in the theory. This result generalize the well known expressions for unitary models. I will provide a general proof, as well as numerical evidence for a non-unitary spin chain (an analytical computation using the corner transfer matrix method for a non-unitary lattice model will be discussed by Davide Bianchini). I will show how a new algebraic technique can be used for studying the branching that arise within the replica approach, and find a new expression for the entanglement entropy in terms of correlation functions of twist fields that is valid for non-unitary models. This expression will be further generalized in Olalla Castro-Alvaredo's talk to the massive Yang-Lee model of integrable quantum field theory.
Primary author
Dr
Benjamin Doyon
(King's College London)
