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Conformal description of near-horizon vacuum states

Banks, Thomas and Zurek, Kathryn M. (2021) Conformal description of near-horizon vacuum states. Physical Review D, 104 (12). Art. No. 126026. ISSN 2470-0010. doi:10.1103/PhysRevD.104.126026.

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Motivated by recent work suggesting observably large spacetime fluctuations in the causal development of an empty region of flat space, we conjecture that these metric fluctuations can be quantitatively described in terms of a conformal field theory of near-horizon vacuum states. One consequence of this conjecture is that fluctuations in the modular Hamiltonian ΔK of a causal diamond are equal to the entanglement entropy: ⟨ΔK²⟩ = ⟨K⟩ = (A(Σ_(d−2))/4G_d, where A(Σ_(d−2)) is the area of the entangling surface in d dimensions. Our conjecture applies to flat space, the cosmological horizon of dS, and AdS Ryu-Takayanagi diamonds, but not to large finite area diamonds in the bulk of AdS. We focus on three pieces of quantitative evidence, from a Randall-Sundrum II braneworld, from the conformal description of black hole horizons, and from the fluid-gravity correspondence. Our hypothesis also suggests that a broader range of formal results can be brought to bear on observables in flat and dS spaces.

Item Type:Article
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URLURL TypeDescription Paper
Banks, Thomas0000-0001-5233-9485
Zurek, Kathryn M.0000-0002-2629-337X
Additional Information:© 2021 Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3. Received 23 August 2021; accepted 6 December 2021; published 28 December 2021. We thank Patrick Draper for collaboration at the early stages of this work, Y. Chen, S. Gukov, V. Lee, D. Li for discussion, and S. Shenker, E. Verlinde, and especially C. Keeler and J. Parra-Martinez for comments on the manuscript. T. B. thanks M. Rangamani, R. Myers and S. Carlip for email discussions of their work. The work of T. B. is partially supported by the Department of Energy under Grant No. DOE SC0010008. The work of K. Z. is supported by the Heising-Simons Foundation “Observational Signatures of Quantum Gravity” collaboration Grant No. 2021-2817, by the DoE under Contract No. DE-SC0011632, and by a Simons Investigator award.
Group:Walter Burke Institute for Theoretical Physics
Funding AgencyGrant Number
Department of Energy (DOE)DE-SC0010008
Heising-Simons Foundation2021-2817
Department of Energy (DOE)DE-SC0011632
Simons FoundationUNSPECIFIED
Issue or Number:12
Record Number:CaltechAUTHORS:20220113-182204467
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:112867
Deposited By: George Porter
Deposited On:13 Jan 2022 21:01
Last Modified:12 Oct 2022 16:01

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