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Title: Two-point correlators revisited: fast and slow scales in multifield models of inflation

Abstract

We study the structure of two-point correlators of the inflationary field fluctuations in order to improve the accuracy and efficiency of the existing methods to calculate primordial spectra. We present a description motivated by the separation of the fast and slow evolving components of the spectrum which is based on Cholesky decomposition of the field correlator matrix. Our purpose is to rewrite all the relevant equations of motion in terms of slowly varying quantities. This is important in order to consider the contribution from high-frequency modes to the spectrum without affecting computational performance. The slow-roll approximation is not required to reproduce the main distinctive features in the power spectrum for each specific model of inflation.

Authors:
;  [1]
  1. Department of Physics, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6 (Canada)
Publication Date:
OSTI Identifier:
22676193
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:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; APPROXIMATIONS; COMPUTERIZED SIMULATION; DECOMPOSITION; EFFICIENCY; EQUATIONS OF MOTION; FLUCTUATIONS; INFLATIONARY UNIVERSE; SPECTRA

Citation Formats

Ghersi, José T. Gálvez, and Frolov, Andrei V., E-mail: joseg@sfu.ca, E-mail: frolov@sfu.ca. Two-point correlators revisited: fast and slow scales in multifield models of inflation. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/05/047.
Ghersi, José T. Gálvez, & Frolov, Andrei V., E-mail: joseg@sfu.ca, E-mail: frolov@sfu.ca. Two-point correlators revisited: fast and slow scales in multifield models of inflation. United States. doi:10.1088/1475-7516/2017/05/047.
Ghersi, José T. Gálvez, and Frolov, Andrei V., E-mail: joseg@sfu.ca, E-mail: frolov@sfu.ca. Mon . "Two-point correlators revisited: fast and slow scales in multifield models of inflation". United States. doi:10.1088/1475-7516/2017/05/047.
@article{osti_22676193,
title = {Two-point correlators revisited: fast and slow scales in multifield models of inflation},
author = {Ghersi, José T. Gálvez and Frolov, Andrei V., E-mail: joseg@sfu.ca, E-mail: frolov@sfu.ca},
abstractNote = {We study the structure of two-point correlators of the inflationary field fluctuations in order to improve the accuracy and efficiency of the existing methods to calculate primordial spectra. We present a description motivated by the separation of the fast and slow evolving components of the spectrum which is based on Cholesky decomposition of the field correlator matrix. Our purpose is to rewrite all the relevant equations of motion in terms of slowly varying quantities. This is important in order to consider the contribution from high-frequency modes to the spectrum without affecting computational performance. The slow-roll approximation is not required to reproduce the main distinctive features in the power spectrum for each specific model of inflation.},
doi = {10.1088/1475-7516/2017/05/047},
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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