skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: On corpuscular theory of inflation

Abstract

In order to go beyond the mean-field approximation, commonly used in the inflationary computations, an identification of the quantum constituents of the inflationary background is made. In particular, the homogeneous scalar field configuration is represented as a Bose–Einstein condensate of the off-shell inflaton degrees of freedom, with mass significantly screened by the gravitational binding energy. The gravitational counterpart of the classical background is considered to be a degenerate state of the off-shell longitudinal gravitons with the frequency of the order of the Hubble scale. As a result, the origin of the density perturbations in the slow-roll regime is identified as an uncertainty in the position of the constituent inflatons. While in the regime of eternal inflation, the scattering of the constituent gravitons becomes the relevant source of the density perturbations. The gravitational waves, on the other hand, originate from the annihilation of the constituent longitudinal gravitons at all energy scales. Lastly, this results in the quantum depletion of the classical background, leading to the upper bound on the number of e-folds, after which the semi-classical description is expected to break down; this is estimated to be of the order of the entropy of the initial Hubble patch.

Authors:
 [1]
  1. Princeton Univ., NJ (United States). Dept. of Physics
Publication Date:
Research Org.:
Princeton Univ., NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1344019
Alternate Identifier(s):
OSTI ID: 1368402
Grant/Contract Number:
SC0007968
Resource Type:
Journal Article: Published Article
Journal Name:
European Physical Journal. C, Particles and Fields
Additional Journal Information:
Journal Volume: 77; Journal Issue: 2; Journal ID: ISSN 1434-6044
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Berezhiani, Lasha. On corpuscular theory of inflation. United States: N. p., 2017. Web. doi:10.1140/epjc/s10052-017-4672-5.
Berezhiani, Lasha. On corpuscular theory of inflation. United States. doi:10.1140/epjc/s10052-017-4672-5.
Berezhiani, Lasha. Thu . "On corpuscular theory of inflation". United States. doi:10.1140/epjc/s10052-017-4672-5.
@article{osti_1344019,
title = {On corpuscular theory of inflation},
author = {Berezhiani, Lasha},
abstractNote = {In order to go beyond the mean-field approximation, commonly used in the inflationary computations, an identification of the quantum constituents of the inflationary background is made. In particular, the homogeneous scalar field configuration is represented as a Bose–Einstein condensate of the off-shell inflaton degrees of freedom, with mass significantly screened by the gravitational binding energy. The gravitational counterpart of the classical background is considered to be a degenerate state of the off-shell longitudinal gravitons with the frequency of the order of the Hubble scale. As a result, the origin of the density perturbations in the slow-roll regime is identified as an uncertainty in the position of the constituent inflatons. While in the regime of eternal inflation, the scattering of the constituent gravitons becomes the relevant source of the density perturbations. The gravitational waves, on the other hand, originate from the annihilation of the constituent longitudinal gravitons at all energy scales. Lastly, this results in the quantum depletion of the classical background, leading to the upper bound on the number of e-folds, after which the semi-classical description is expected to break down; this is estimated to be of the order of the entropy of the initial Hubble patch.},
doi = {10.1140/epjc/s10052-017-4672-5},
journal = {European Physical Journal. C, Particles and Fields},
number = 2,
volume = 77,
place = {United States},
year = {Thu Feb 16 00:00:00 EST 2017},
month = {Thu Feb 16 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1140/epjc/s10052-017-4672-5

Citation Metrics:
Cited by: 2works
Citation information provided by
Web of Science

Save / Share:
  • In order to go beyond the mean-field approximation, commonly used in the inflationary computations, an identification of the quantum constituents of the inflationary background is made. In particular, the homogeneous scalar field configuration is represented as a Bose–Einstein condensate of the off-shell inflaton degrees of freedom, with mass significantly screened by the gravitational binding energy. The gravitational counterpart of the classical background is considered to be a degenerate state of the off-shell longitudinal gravitons with the frequency of the order of the Hubble scale. As a result, the origin of the density perturbations in the slow-roll regime is identified asmore » an uncertainty in the position of the constituent inflatons. While in the regime of eternal inflation, the scattering of the constituent gravitons becomes the relevant source of the density perturbations. The gravitational waves, on the other hand, originate from the annihilation of the constituent longitudinal gravitons at all energy scales. Lastly, this results in the quantum depletion of the classical background, leading to the upper bound on the number of e-folds, after which the semi-classical description is expected to break down; this is estimated to be of the order of the entropy of the initial Hubble patch.« less
  • A corpuscular quantum description of inflation shows that there is no fundamental problem with trans-Planckian excursions of the inflaton field up to about 100 Planck masses, with the upper bound coming from the corpuscular quantum effects. In this description, the r parameter measures the ratio of occupation numbers of gravitons versus inflatons, which, according to BICEP2, was roughly a half at the time of 60 e-foldings prior to the end of inflation. We stress that in a non-Wilsonian UV self-completion of gravity, any trans-Planckian mode coupled to the inflaton is a black hole. Unlike the Wilsonian case, integrating them outmore » gives an exponentially suppressed effect and is unable to prevent trans-Planckian excursions of the inflaton field.« less
  • The general vector field is formulated in a matrix representation with a first-order wave equation. It is then shown explicitiy how its two spin states 1 and 0 are mixed together. On the other hand, the general vector field obeys an algebraic law which is different from that of the irreducible fields of spin 1 and 0, though these fields are just the two spin components of the general vector field. This algebra constitutes therefore a new way in the formulation of a general mixed theory of the spins 1 and 0. Finally, a comparison is made between the generalmore » vector field and the field of maximum spin l of the fusion theory as concerning their internal structure with regard to spin states. (auth)« less