A note on transPlanckian 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 backreaction of the set of tail modes in a theory with a dispersion relation in which the mode frequency decays exponentially in the transPlanckian regime. The matter tail modes are frozen out, however they induce metric fluctuations. The energymomentum 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 superHubble 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:
 Department of Physics, McGill University,3600 University Street, Montréal, QC, H3A 2T8 (Canada)
 (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: PUBLISHERID: 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; ENERGYMOMENTUM 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, 05508090, and Brandenberger, R. A note on transPlanckian tail effects. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/09/032.
Graef, L.L., Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508090, & Brandenberger, R. A note on transPlanckian tail effects. United States. doi:10.1088/14757516/2015/09/032.
Graef, L.L., Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508090, and Brandenberger, R. 2015.
"A note on transPlanckian tail effects". United States.
doi:10.1088/14757516/2015/09/032.
@article{osti_22458374,
title = {A note on transPlanckian tail effects},
author = {Graef, L.L. and Instituto de Física, Universidade de São Paulo, Rua do Matão travessa R, São Paulo, SP, 05508090 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 backreaction of the set of tail modes in a theory with a dispersion relation in which the mode frequency decays exponentially in the transPlanckian regime. The matter tail modes are frozen out, however they induce metric fluctuations. The energymomentum 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 superHubble 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 = {10.1088/14757516/2015/09/032},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 09,
volume = 2015,
place = {United States},
year = 2015,
month = 9
}

We study the proposal by Mersini et al. [1] that the observed dark energy might be explained by the backreaction of the set of tail modes in a theory with a dispersion relation in which the mode frequency decays exponentially in the transPlanckian regime. The matter tail modes are frozen out, however they induce metric fluctuations. The energymomentum 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 »

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