Speaker
Jin-Yi Pang
(National Taiwan University)
Description
We investigate how entanglement entropy behaves in general non-conformal
quantum field theories which describe kinds of physical systems. The
scalar field in $O(N)$ $\sigma-$model and non-Abelian $SU(N)$ gauge
field on lattice are concerned as two typical bosonic models in our
study. By virtue of divergency structure of entanglement entropy,
we distinguish different phases of $O(N)$ $\sigma-$model, symmetric
phase with positive mass square and symmetry-breaking phase with negative
one. The ultra-violet divergences in entanglement entropy of field
theories, further more, are demonstrated to be cancelled by counter-terms
induced on the interface between two subregions entangling to each
other. It is consistent with that topological entanglement entropy
as non-divergent part of entanglement entropy is renormalizable quantity
which is understood as cosmological constant living on interface.
In non-Abelian $SU(N)$ gauge field theories, at the same time, interface
cosmological constant becomes more important because it is able to
clarify ambiguity emerging from different choices of boundary conditions
on the interface in gauge field theories simultaneously. In order
to extract physical quantity from the disputed issue, we continue
to calculate finite temperature dependence, susceptivity to size of
subsystem and mutual information which are related to physical parts
of entanglement and as well irrelevant to interface counter-terms.
(Based on arXiv: 1411.2916, arXiv: 1503.01766 and a prepared paper.)
Primary author
Jin-Yi Pang
(National Taiwan University)
Co-authors
Jiunn-Wei Chen
Shou-Huang Dai
(N)
