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Title: Entanglement entropy and decoupling in the Universe

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 96; Journal Issue: 12; Related Information: CHORUS Timestamp: 2017-12-15 10:32:00; Journal ID: ISSN 2470-0010
American Physical Society
Country of Publication:
United States

Citation Formats

Nakai, Yuichiro, Shiba, Noburo, and Yamada, Masaki. Entanglement entropy and decoupling in the Universe. United States: N. p., 2017. Web. doi:10.1103/PhysRevD.96.123518.
Nakai, Yuichiro, Shiba, Noburo, & Yamada, Masaki. Entanglement entropy and decoupling in the Universe. United States. doi:10.1103/PhysRevD.96.123518.
Nakai, Yuichiro, Shiba, Noburo, and Yamada, Masaki. 2017. "Entanglement entropy and decoupling in the Universe". United States. doi:10.1103/PhysRevD.96.123518.
title = {Entanglement entropy and decoupling in the Universe},
author = {Nakai, Yuichiro and Shiba, Noburo and Yamada, Masaki},
abstractNote = {},
doi = {10.1103/PhysRevD.96.123518},
journal = {Physical Review D},
number = 12,
volume = 96,
place = {United States},
year = 2017,
month =

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on December 15, 2018
Publisher's Accepted Manuscript

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  • We investigate the entropy evolution in the early universe by computing the change of the entanglement entropy in Freedmann-Robertson-Walker quantum cosmology in the presence of particle horizon. The matter is modeled by a Chaplygin gas so as to provide a smooth interpolation between inflationary and radiation epochs, rendering the evolution of entropy from early time to late time trackable. We found that soon after the onset of the inflation, the total entanglement entropy rapidly decreases to a minimum. It then rises monotonically in the remainder of the inflation epoch as well as the radiation epoch. Our result is in qualitativemore » agreement with the area law of Ryu and Takayanagi including the logarithmic correction. We comment on the possible implication of our finding to the cosmological entropy problem.« less
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