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Title: Ghost inflation and de Sitter entropy

Abstract

In the setup of ghost condensation model the generalized second law of black hole thermodynamics can be respected under a radiatively stable assumption that couplings between the field responsible for ghost condensate and matter fields such as those in the Standard Model are suppressed by the Planck scale. Since not only black holes but also cosmology are expected to play important roles towards our better understanding of gravity, we consider a cosmological setup to test the theory of ghost condensation. In particular we shall show that the de Sitter entropy bound proposed by Arkani-Hamed, et al. is satisfied if ghost inflation happened in the early epoch of our universe and if there remains a tiny positive cosmological constant in the future infinity. We then propose a notion of cosmological Page time after inflation.

Authors:
 [1];  [2];  [3];  [4];  [5];  [6]
  1. School of Astronomy, Institute for Research in Fundamental Sciences (IPM),P.O. Box 19395-5531, Artesh Highway, Tehran (Iran, Islamic Republic of)
  2. Center for Gravitational Physics, Yukawa Institute for Theoretical Physics,Kyoto University,606-8502, Kyoto (Japan)
  3. (WPI),The University of Tokyo Institutes for Advanced Study, The University of Tokyo,Kashiwa, Chiba 277-8583 (Japan)
  4. School of Physics, Huazhong University of Science and Technology,Wuhan 430074 (China)
  5. Kavli Institute for the Physics and Mathematics of the Universe (WPI),The University of Tokyo Institutes for Advanced Study, The University of Tokyo,Kashiwa, Chiba 277-8583 (Japan)
  6. (Japan)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22572125
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 08; Other Information: PUBLISHER-ID: JCAP08(2016)002; OAI: oai:repo.scoap3.org:16637; cc-by Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BLACK HOLES; COSMOLOGICAL CONSTANT; COSMOLOGICAL INFLATION; COSMOLOGY; DE SITTER GROUP; DE SITTER SPACE; ENTROPY; INFLATIONARY UNIVERSE; PERTURBATION THEORY; STANDARD MODEL

Citation Formats

Jazayeri, Sadra, Mukohyama, Shinji, Kavli Institute for the Physics and Mathematics of the Universe, Saitou, Rio, Watanabe, Yota, and Center for Gravitational Physics, Yukawa Institute for Theoretical Physics,Kyoto University,606-8502, Kyoto. Ghost inflation and de Sitter entropy. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/08/002.
Jazayeri, Sadra, Mukohyama, Shinji, Kavli Institute for the Physics and Mathematics of the Universe, Saitou, Rio, Watanabe, Yota, & Center for Gravitational Physics, Yukawa Institute for Theoretical Physics,Kyoto University,606-8502, Kyoto. Ghost inflation and de Sitter entropy. United States. doi:10.1088/1475-7516/2016/08/002.
Jazayeri, Sadra, Mukohyama, Shinji, Kavli Institute for the Physics and Mathematics of the Universe, Saitou, Rio, Watanabe, Yota, and Center for Gravitational Physics, Yukawa Institute for Theoretical Physics,Kyoto University,606-8502, Kyoto. 2016. "Ghost inflation and de Sitter entropy". United States. doi:10.1088/1475-7516/2016/08/002.
@article{osti_22572125,
title = {Ghost inflation and de Sitter entropy},
author = {Jazayeri, Sadra and Mukohyama, Shinji and Kavli Institute for the Physics and Mathematics of the Universe and Saitou, Rio and Watanabe, Yota and Center for Gravitational Physics, Yukawa Institute for Theoretical Physics,Kyoto University,606-8502, Kyoto},
abstractNote = {In the setup of ghost condensation model the generalized second law of black hole thermodynamics can be respected under a radiatively stable assumption that couplings between the field responsible for ghost condensate and matter fields such as those in the Standard Model are suppressed by the Planck scale. Since not only black holes but also cosmology are expected to play important roles towards our better understanding of gravity, we consider a cosmological setup to test the theory of ghost condensation. In particular we shall show that the de Sitter entropy bound proposed by Arkani-Hamed, et al. is satisfied if ghost inflation happened in the early epoch of our universe and if there remains a tiny positive cosmological constant in the future infinity. We then propose a notion of cosmological Page time after inflation.},
doi = {10.1088/1475-7516/2016/08/002},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2016,
place = {United States},
year = 2016,
month = 8
}
  • The propagators of the Faddeev-Popov (FP) ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge are infrared (IR) divergent in de Sitter spacetime. We point out, however, that the modes responsible for these divergences will not contribute to loop diagrams in computations of time-ordered products in either Yang-Mills theories or perturbative quantum gravity. Therefore, we propose that the IR-divergent FP-ghost propagator should be regularized by a small mass term that is sent to zero in the end of any perturbative calculations. This proposal is equivalent to using the effective FP-ghost propagators, which we present in an explicitmore » form, obtained by removing the modes responsible for the IR divergences. We also make some comments on the corresponding propagators in anti-de Sitter spacetime.« less
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  • We present a setup that provides a partial UV-completion of the ghost inflation model up to a scale which can be almost as high as the Planck mass. This is achieved by coupling the inflaton to the Lorentz-violating sector described by the Einstein-aether theory or its khronometric version. Compared to previous works on ghost inflation our setup allows to go beyond the study of small perturbations and include the background dynamics in a unified framework. In the specific regime when the expansion of the Universe is dominated by the kinetic energy of the inflaton we find that the model predictsmore » rather high tensor-to-scalar ratio r ∼ 0.02÷0.2 and non-Gaussianity of equilateral type with f{sub NL} in the range from -50 to -5.« less