Entanglement branes in a twodimensional string theory
Abstract
What is the meaning of entanglement in a theory of extended objects such as strings? To address this question we consider the spatial entanglement between two intervals in the GrossTaylor model, the string theory dual to twodimensional YangMills theory at large N. The string diagrams that contribute to the entanglement entropy describe open strings with endpoints anchored to the entangling surface, as first argued by Susskind. We develop a canonical theory of these open strings, and describe how closed strings are divided into open strings at the level of the Hilbert space. Here, we derive the modular Hamiltonian for the HartleHawking state and show that the corresponding reduced density matrix describes a thermal ensemble of open strings ending on an object at the entangling surface that we call an entanglement brane, or Ebrane.
 Authors:
 Univ. of California, Santa Barbara, CA (United States). Dept. of Physics
 Univ. of Virginia, Charlottesville, VA (United States). Dept. of Physics
 Publication Date:
 Research Org.:
 Univ. of California, Santa Barbara, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1424734
 Grant/Contract Number:
 SC0011702
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Journal of High Energy Physics (Online)
 Additional Journal Information:
 Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2017; Journal Issue: 9; Journal ID: ISSN 10298479
 Publisher:
 Springer Berlin
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 1/N Expansion; Dbranes; Topological Field Theories; Topological Strings
Citation Formats
Donnelly, William, and Wong, Gabriel. Entanglement branes in a twodimensional string theory. United States: N. p., 2017.
Web. doi:10.1007/JHEP09(2017)097.
Donnelly, William, & Wong, Gabriel. Entanglement branes in a twodimensional string theory. United States. doi:10.1007/JHEP09(2017)097.
Donnelly, William, and Wong, Gabriel. 2017.
"Entanglement branes in a twodimensional string theory". United States.
doi:10.1007/JHEP09(2017)097. https://www.osti.gov/servlets/purl/1424734.
@article{osti_1424734,
title = {Entanglement branes in a twodimensional string theory},
author = {Donnelly, William and Wong, Gabriel},
abstractNote = {What is the meaning of entanglement in a theory of extended objects such as strings? To address this question we consider the spatial entanglement between two intervals in the GrossTaylor model, the string theory dual to twodimensional YangMills theory at large N. The string diagrams that contribute to the entanglement entropy describe open strings with endpoints anchored to the entangling surface, as first argued by Susskind. We develop a canonical theory of these open strings, and describe how closed strings are divided into open strings at the level of the Hilbert space. Here, we derive the modular Hamiltonian for the HartleHawking state and show that the corresponding reduced density matrix describes a thermal ensemble of open strings ending on an object at the entangling surface that we call an entanglement brane, or Ebrane.},
doi = {10.1007/JHEP09(2017)097},
journal = {Journal of High Energy Physics (Online)},
number = 9,
volume = 2017,
place = {United States},
year = 2017,
month = 9
}

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