Title: Crosscap States in Integrable Field Theories and Spin Chains
Speaker: Shota Komatsu
Affiliation: CERN（欧洲核子研究中心）
Time: 16:00-17:00, Tuesday, 7th June, 2022 (UTC+8, Beijing Time)
Venue: Zoom Meeting
Inviter: Yunfeng JIANG （江云峰）
Abstract
Crosscap states have been studied extensively in two-dimensional conformal field theory in the past, where part of the motivations came from their connection to orientifolds in string theory. Surprisingly however, analogous studies in (massive) integrable theories have been lacking. In this talk, I will fill this gap by presenting a systematic study of crosscap states in integrable field theories and spin chains. First, I derive an exact formula for overlaps between the crosscap state and any excited state in integrable field theories with diagonal scattering. Using the formula, I compute the crosscap entropy i.e. the overlap with the ground state in several examples, and find that it decreases monotonically along the renormalization group flow except in cases where the discrete symmetry is spontaneously broken in the infrared. We next introduce crosscap states in integrable spin chains and obtain exact determinant expressions for overlaps with energy eigenstates. These states are long-range entangled and provide interesting initial conditions for the quantum quench protocol, which are quite distinct from short-range entangled states corresponding to the boundary states.
About the Speaker
Shota Komatsu is currently a scientific staff researcher at the Department of Theoretical Physics of CERN. He received his Ph.D. from the University of Tokyo in 2014 and then worked as a postdoc at Perimeter Institute for Theoretical Physics in Canada (2014 - 2017) and as a postdoc at the Institute for Advanced Study (IAS), Princeton (2017 to 2020). In 2020, he joined the Department of Theoretical Physics of CERN.
His fields of interest includes Quantum Field Theory, String Theory and integrability.
The seminar will be broadcasted online by Zoom.
Interested people are free to join, without registration in advance.
The Zoom info is
URL: https://us02web.zoom.us/j/3854420225?pwd=SXY4eWJKOTBFZWJDaE16aXpTamY1QT09
Meeting ID: 385 442 0225
Passcode: yauc