Asymptotic symmetries in de Sitter and inflationary spacetimes
Abstract
Soft gravitons produced by the expansion of de Sitter can be viewed as the NambuGoldstone bosons of spontaneously broken asymptotic symmetries of the de Sitter spacetime. We explicitly construct the associated charges, and show that acting with the charges on the vacuum creates a new state equivalent to a change in the local coordinates induced by the soft graviton. While the effect remains unobservable within the domain of a single observer where the symmetry is unbroken, this change is physical when comparing different asymptotic observers, or between a transformed and untransformed initial state, consistent with the scaledependent statistical anisotropies previously derived using semiclassical relations. We then compute the overlap, (0 0'), between the unperturbed de Sitter vacuum 0), and the state  0') obtained by acting N times with the charge. We show that when N→ M {sub p} {sup 2}/ H {sup 2} this overlap receives order one corrections and 0(0 0')→ , which corresponds to an infrared perturbative breakdown after a time t {sub dS} ∼ M {sub p} {sup 2}/ H {sup 3} has elapsed, consistent with earlier arguments in the literature arguing for a perturbative breakdown on this timescale. We also discuss the generalization to inflation,more »
 Authors:
 CP3Origins, Center for Cosmology and Particle Physics Phenomenology, University of Southern Denmark, Campusvej 55, 5230 Odense M (Denmark)
 Publication Date:
 OSTI Identifier:
 22679909
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; ASYMPTOTIC SOLUTIONS; BREAKDOWN; COMPARATIVE EVALUATIONS; D S MESONS; DE SITTER SPACE; EXPANSION; GOLDSTONE BOSONS; GRAVITONS; INFLATIONARY UNIVERSE; SEMICLASSICAL APPROXIMATION; SPACETIME; SYMMETRY BREAKING
Citation Formats
Ferreira, Ricardo Z., Sandora, McCullen, and Sloth, Martin S., Email: ferreira@cp3.sdu.dk, Email: sandora@cp3.sdu.dk, Email: sloth@cp3.sdu.dk. Asymptotic symmetries in de Sitter and inflationary spacetimes. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/04/033.
Ferreira, Ricardo Z., Sandora, McCullen, & Sloth, Martin S., Email: ferreira@cp3.sdu.dk, Email: sandora@cp3.sdu.dk, Email: sloth@cp3.sdu.dk. Asymptotic symmetries in de Sitter and inflationary spacetimes. United States. doi:10.1088/14757516/2017/04/033.
Ferreira, Ricardo Z., Sandora, McCullen, and Sloth, Martin S., Email: ferreira@cp3.sdu.dk, Email: sandora@cp3.sdu.dk, Email: sloth@cp3.sdu.dk. Sat .
"Asymptotic symmetries in de Sitter and inflationary spacetimes". United States.
doi:10.1088/14757516/2017/04/033.
@article{osti_22679909,
title = {Asymptotic symmetries in de Sitter and inflationary spacetimes},
author = {Ferreira, Ricardo Z. and Sandora, McCullen and Sloth, Martin S., Email: ferreira@cp3.sdu.dk, Email: sandora@cp3.sdu.dk, Email: sloth@cp3.sdu.dk},
abstractNote = {Soft gravitons produced by the expansion of de Sitter can be viewed as the NambuGoldstone bosons of spontaneously broken asymptotic symmetries of the de Sitter spacetime. We explicitly construct the associated charges, and show that acting with the charges on the vacuum creates a new state equivalent to a change in the local coordinates induced by the soft graviton. While the effect remains unobservable within the domain of a single observer where the symmetry is unbroken, this change is physical when comparing different asymptotic observers, or between a transformed and untransformed initial state, consistent with the scaledependent statistical anisotropies previously derived using semiclassical relations. We then compute the overlap, (0 0'), between the unperturbed de Sitter vacuum 0), and the state  0') obtained by acting N times with the charge. We show that when N→ M {sub p} {sup 2}/ H {sup 2} this overlap receives order one corrections and 0(0 0')→ , which corresponds to an infrared perturbative breakdown after a time t {sub dS} ∼ M {sub p} {sup 2}/ H {sup 3} has elapsed, consistent with earlier arguments in the literature arguing for a perturbative breakdown on this timescale. We also discuss the generalization to inflation, and rederive the 3point and oneloop consistency relations.},
doi = {10.1088/14757516/2017/04/033},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2017,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}

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