Tensor perturbations during inflation in a spatially closed Universe
Abstract
In a recent paper [1], we studied the evolution of the background geometry and scalar perturbations in an inflationary, spatially closed FriedmannLemaȋtreRobertsonWalker (FLRW) model having constant positive spatial curvature and spatial topology S{sup 3}. Due to the spatial curvature, the early phase of slowroll inflation is modified, leading to suppression of power in the scalar power spectrum at large angular scales. In this paper, we extend the analysis to include tensor perturbations. We find that, similarly to the scalar perturbations, the tensor power spectrum also shows suppression for long wavelength modes. The correction to the tensor spectrum is limited to the very long wavelength modes, therefore the resulting observable CMB Bmode polarization spectrum remains practically the same as in the standard scenario with flat spatial sections. However, since both the tensor and scalar power spectra are modified, there are scale dependent corrections to the tensortoscalar ratio that leads to violation of the standard slowroll consistency relation.
 Authors:
 Institute for Gravitation and the Cosmos and Physics Department, The Pennsylvania State University, 104 Lavey Lab, University Park, PA 16802 (United States)
 Publication Date:
 OSTI Identifier:
 22676218
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DISTURBANCES; EVOLUTION; INFLATIONARY UNIVERSE; PERTURBATION THEORY; POLARIZATION; RELICT RADIATION; SPECTRA; UNIVERSE; WAVELENGTHS
Citation Formats
Bonga, Béatrice, Gupt, Brajesh, and Yokomizo, Nelson, Email: bpb165@psu.edu, Email: bgupt@gravity.psu.edu, Email: yokomizo@gravity.psu.edu. Tensor perturbations during inflation in a spatially closed Universe. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/05/021.
Bonga, Béatrice, Gupt, Brajesh, & Yokomizo, Nelson, Email: bpb165@psu.edu, Email: bgupt@gravity.psu.edu, Email: yokomizo@gravity.psu.edu. Tensor perturbations during inflation in a spatially closed Universe. United States. doi:10.1088/14757516/2017/05/021.
Bonga, Béatrice, Gupt, Brajesh, and Yokomizo, Nelson, Email: bpb165@psu.edu, Email: bgupt@gravity.psu.edu, Email: yokomizo@gravity.psu.edu. Mon .
"Tensor perturbations during inflation in a spatially closed Universe". United States.
doi:10.1088/14757516/2017/05/021.
@article{osti_22676218,
title = {Tensor perturbations during inflation in a spatially closed Universe},
author = {Bonga, Béatrice and Gupt, Brajesh and Yokomizo, Nelson, Email: bpb165@psu.edu, Email: bgupt@gravity.psu.edu, Email: yokomizo@gravity.psu.edu},
abstractNote = {In a recent paper [1], we studied the evolution of the background geometry and scalar perturbations in an inflationary, spatially closed FriedmannLemaȋtreRobertsonWalker (FLRW) model having constant positive spatial curvature and spatial topology S{sup 3}. Due to the spatial curvature, the early phase of slowroll inflation is modified, leading to suppression of power in the scalar power spectrum at large angular scales. In this paper, we extend the analysis to include tensor perturbations. We find that, similarly to the scalar perturbations, the tensor power spectrum also shows suppression for long wavelength modes. The correction to the tensor spectrum is limited to the very long wavelength modes, therefore the resulting observable CMB Bmode polarization spectrum remains practically the same as in the standard scenario with flat spatial sections. However, since both the tensor and scalar power spectra are modified, there are scale dependent corrections to the tensortoscalar ratio that leads to violation of the standard slowroll consistency relation.},
doi = {10.1088/14757516/2017/05/021},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2017,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}

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