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Title: Compactly supported linearised observables in single-field inflation

Abstract

We investigate the gauge-invariant observables constructed by smearing the graviton and inflaton fields by compactly supported tensors at linear order in general single-field inflation. These observables correspond to gauge-invariant quantities that can be measured locally. In particular, we show that these observables are equivalent to (smeared) local gauge-invariant observables such as the linearised Weyl tensor, which have better infrared properties than the graviton and inflaton fields. Special cases include the equivalence between the compactly supported gauge-invariant graviton observable and the smeared linearised Weyl tensor in Minkowski and de Sitter spaces. Our results indicate that the infrared divergences in the tensor and scalar perturbations in single-field inflation have the same status as in de Sitter space and are both a gauge artefact, in a certain technical sense, at tree level.

Authors:
;  [1];  [2]
  1. Department of Mathematics, University of York, Heslington, York, YO10 5DD (United Kingdom)
  2. Institut für Theoretische Physik, Universität Leipzig, Brüderstraße 16, 04103 Leipzig (Germany)
Publication Date:
OSTI Identifier:
22676050
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 07; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; DE SITTER SPACE; DISTURBANCES; FIELD THEORIES; GAUGE INVARIANCE; GRAVITONS; INFLATONS; INFRARED DIVERGENCES; MINKOWSKI SPACE; PERTURBATION THEORY; WEYL UNIFIED THEORY

Citation Formats

Fröob, Markus B., Higuchi, Atsushi, and Hack, Thomas-Paul, E-mail: mbf503@york.ac.uk, E-mail: thomas-paul.hack@itp.uni-leipzig.de, E-mail: atsushi.higuchi@york.ac.uk. Compactly supported linearised observables in single-field inflation. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/07/043.
Fröob, Markus B., Higuchi, Atsushi, & Hack, Thomas-Paul, E-mail: mbf503@york.ac.uk, E-mail: thomas-paul.hack@itp.uni-leipzig.de, E-mail: atsushi.higuchi@york.ac.uk. Compactly supported linearised observables in single-field inflation. United States. doi:10.1088/1475-7516/2017/07/043.
Fröob, Markus B., Higuchi, Atsushi, and Hack, Thomas-Paul, E-mail: mbf503@york.ac.uk, E-mail: thomas-paul.hack@itp.uni-leipzig.de, E-mail: atsushi.higuchi@york.ac.uk. Sat . "Compactly supported linearised observables in single-field inflation". United States. doi:10.1088/1475-7516/2017/07/043.
@article{osti_22676050,
title = {Compactly supported linearised observables in single-field inflation},
author = {Fröob, Markus B. and Higuchi, Atsushi and Hack, Thomas-Paul, E-mail: mbf503@york.ac.uk, E-mail: thomas-paul.hack@itp.uni-leipzig.de, E-mail: atsushi.higuchi@york.ac.uk},
abstractNote = {We investigate the gauge-invariant observables constructed by smearing the graviton and inflaton fields by compactly supported tensors at linear order in general single-field inflation. These observables correspond to gauge-invariant quantities that can be measured locally. In particular, we show that these observables are equivalent to (smeared) local gauge-invariant observables such as the linearised Weyl tensor, which have better infrared properties than the graviton and inflaton fields. Special cases include the equivalence between the compactly supported gauge-invariant graviton observable and the smeared linearised Weyl tensor in Minkowski and de Sitter spaces. Our results indicate that the infrared divergences in the tensor and scalar perturbations in single-field inflation have the same status as in de Sitter space and are both a gauge artefact, in a certain technical sense, at tree level.},
doi = {10.1088/1475-7516/2017/07/043},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 07,
volume = 2017,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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