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Title: A note on trans-Planckian tail effects

Abstract

We study the proposal by Mersini et al. http://dx.doi.org/10.1103/PhysRevD.64.043508 that the observed dark energy might be explained by the back-reaction of the set of tail modes in a theory with a dispersion relation in which the mode frequency decays exponentially in the trans-Planckian regime. The matter tail modes are frozen out, however they induce metric fluctuations. The energy-momentum tensor with which the tail modes effect the background geometry obtains contributions from both metric and matter fluctuations. We calculate the equation of state induced by the tail modes taking into account the gravitational contribution. We find that, in contrast to the case of frozen super-Hubble cosmological fluctuations, in this case the matter perturbations dominate, and they yield an equation of state which to leading order takes the form of a positive cosmological constant.

Authors:
 [1];  [2];  [1]
  1. Department of Physics, McGill University,3600 University Street, Montréal, QC, H3A 2T8 (Canada)
  2. (Brazil)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22458374
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 09; Other Information: PUBLISHER-ID: JCAP09(2015)032; OAI: oai:repo.scoap3.org:11744; 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:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMOLOGICAL CONSTANT; COSMOLOGICAL INFLATION; DISPERSION RELATIONS; ENERGY-MOMENTUM TENSOR; EQUATIONS OF STATE; FLUCTUATIONS; METRICS; NONLUMINOUS MATTER; PERTURBATION THEORY; STRING MODELS; UNIVERSE

Citation Formats

Graef, L.L., Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508-090, and Brandenberger, R. A note on trans-Planckian tail effects. United States: N. p., 2015. Web. doi:10.1088/1475-7516/2015/09/032.
Graef, L.L., Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508-090, & Brandenberger, R. A note on trans-Planckian tail effects. United States. doi:10.1088/1475-7516/2015/09/032.
Graef, L.L., Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508-090, and Brandenberger, R. Wed . "A note on trans-Planckian tail effects". United States. doi:10.1088/1475-7516/2015/09/032.
@article{osti_22458374,
title = {A note on trans-Planckian tail effects},
author = {Graef, L.L. and Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508-090 and Brandenberger, R.},
abstractNote = {We study the proposal by Mersini et al. http://dx.doi.org/10.1103/PhysRevD.64.043508 that the observed dark energy might be explained by the back-reaction of the set of tail modes in a theory with a dispersion relation in which the mode frequency decays exponentially in the trans-Planckian regime. The matter tail modes are frozen out, however they induce metric fluctuations. The energy-momentum tensor with which the tail modes effect the background geometry obtains contributions from both metric and matter fluctuations. We calculate the equation of state induced by the tail modes taking into account the gravitational contribution. We find that, in contrast to the case of frozen super-Hubble cosmological fluctuations, in this case the matter perturbations dominate, and they yield an equation of state which to leading order takes the form of a positive cosmological constant.},
doi = {10.1088/1475-7516/2015/09/032},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 09,
volume = 2015,
place = {United States},
year = {Wed Sep 09 00:00:00 EDT 2015},
month = {Wed Sep 09 00:00:00 EDT 2015}
}
  • We study the proposal by Mersini et al. [1] that the observed dark energy might be explained by the back-reaction of the set of tail modes in a theory with a dispersion relation in which the mode frequency decays exponentially in the trans-Planckian regime. The matter tail modes are frozen out, however they induce metric fluctuations. The energy-momentum tensor with which the tail modes effect the background geometry obtains contributions from both metric and matter fluctuations. We calculate the equation of state induced by the tail modes taking into account the gravitational contribution. We find that, in contrast to themore » case of frozen super-Hubble cosmological fluctuations, in this case the matter perturbations dominate, and they yield an equation of state which to leading order takes the form of a positive cosmological constant.« less
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