Spacetime from unentanglement
The past decade has seen a tremendous effort toward unraveling the relationship between entanglement and emergent spacetime. These investigations have revealed that entanglement between holographic degrees of freedom is crucial for the existence of bulk spacetime. We examine this connection from the other end of the entanglement spectrum and clarify the assertion that maximally entangled states have no reconstructable spacetime. To do so, we first define the conditions for bulk reconstructability. Under these terms, we scrutinize two cases of maximally entangled holographic states. One is the familiar example of AdS black holes; these are dual to thermal states of the boundary conformal field theory. Sending the temperature to the cutoff scale makes the state maximally entangled and the respective black hole consumes the spacetime. We then examine the de Sitter limit of FriedmannRobertsonWalker (FRW) spacetimes. This limit is maximally entangled if one formulates the boundary theory on the holographic screen. Paralleling the antide Sitter (AdS) black hole, we find the resulting reconstructable region of spacetime vanishes. Motivated by these results, we prove a theorem showing that maximally entangled states have no reconstructable spacetime. Evidently, the emergence of spacetime is endemic to intermediate entanglement. By studying the manner in which intermediatemore »
 Authors:

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 Univ. of California, Berkeley, CA (United States). Berkeley Center for Theoretical Physics, Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of Tokyo, Kashiwa (Japan). Kavli Inst. for the Physics and Mathematics of the Universe (WPI)
 Univ. of California, Berkeley, CA (United States). Berkeley Center for Theoretical Physics, Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
 Publication Date:
 Grant/Contract Number:
 AC0205CH11231; 15H05895; PHY1521446
 Type:
 Published Article
 Journal Name:
 Physical Review D
 Additional Journal Information:
 Journal Volume: 97; Journal Issue: 10; Journal ID: ISSN 24700010
 Publisher:
 American Physical Society (APS)
 Research Org:
 Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25); National Science Foundation (NSF)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTRONOMY AND ASTROPHYSICS
 OSTI Identifier:
 1437327
 Alternate Identifier(s):
 OSTI ID: 1461147
Nomura, Yasunori, Rath, Pratik, and Salzetta, Nico. Spacetime from unentanglement. United States: N. p.,
Web. doi:10.1103/PhysRevD.97.106010.
Nomura, Yasunori, Rath, Pratik, & Salzetta, Nico. Spacetime from unentanglement. United States. doi:10.1103/PhysRevD.97.106010.
Nomura, Yasunori, Rath, Pratik, and Salzetta, Nico. 2018.
"Spacetime from unentanglement". United States.
doi:10.1103/PhysRevD.97.106010.
@article{osti_1437327,
title = {Spacetime from unentanglement},
author = {Nomura, Yasunori and Rath, Pratik and Salzetta, Nico},
abstractNote = {The past decade has seen a tremendous effort toward unraveling the relationship between entanglement and emergent spacetime. These investigations have revealed that entanglement between holographic degrees of freedom is crucial for the existence of bulk spacetime. We examine this connection from the other end of the entanglement spectrum and clarify the assertion that maximally entangled states have no reconstructable spacetime. To do so, we first define the conditions for bulk reconstructability. Under these terms, we scrutinize two cases of maximally entangled holographic states. One is the familiar example of AdS black holes; these are dual to thermal states of the boundary conformal field theory. Sending the temperature to the cutoff scale makes the state maximally entangled and the respective black hole consumes the spacetime. We then examine the de Sitter limit of FriedmannRobertsonWalker (FRW) spacetimes. This limit is maximally entangled if one formulates the boundary theory on the holographic screen. Paralleling the antide Sitter (AdS) black hole, we find the resulting reconstructable region of spacetime vanishes. Motivated by these results, we prove a theorem showing that maximally entangled states have no reconstructable spacetime. Evidently, the emergence of spacetime is endemic to intermediate entanglement. By studying the manner in which intermediate entanglement is achieved, we uncover important properties about the boundary theory of FRW spacetimes. With this clarified understanding, our final discussion elucidates the natural way in which holographic Hilbert spaces may house states dual to different geometries. Here, this paper provides a coherent picture clarifying the link between spacetime and entanglement and develops many promising avenues of further work.},
doi = {10.1103/PhysRevD.97.106010},
journal = {Physical Review D},
number = 10,
volume = 97,
place = {United States},
year = {2018},
month = {5}
}