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Title: IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence

Abstract

Because large-scale structure surveys may very well be the next leading sources of cosmological information, it is important to have a precise understanding of the cosmological observables; for this reason, the Effective Field Theory of Large-Scale Structure (EFTofLSS) was developed. So far, most results in the EFTofLSS have used the so-called Einstein-de Sitter approximation, an approximation of the time dependence which is known to be accurate to better than one percent. However, in order to reach even higher accuracy, the full time dependence must be used. The computation with exact time dependence is sensitive to both infrared (IR) and ultraviolet (UV) effects in the loop integrands, and while these effects must cancel because of diffeomorphism invariance, they make numerical computation much less efficient. We provide a formulation of the one-loop, equal-time exact-time-dependence power spectrum of density perturbations which is manifestly free of these spurious IR and UV divergences at the level of the integrand. We extend our results to the total matter mode with clustering quintessence, show that IR and UV divergences cancel, and provide the associated IR- and UV-safe integrand. This also establishes that the consistency conditions are satisfied in this system. In conclusion, we then use our one-loopmore » result to do an improved precision comparison of the two-loop dark-matter power spectrum with the Dark Sky N-body simulation.« less

Authors:
 [1];  [2]
  1. Univ. Paris Saclay, Gif-sur-Yvette (France)
  2. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1394080
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2017; Journal Issue: 08; Journal ID: ISSN 1475-7516
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; dark energy theory; dark matter theory; power spectrum

Citation Formats

Lewandowski, Matthew, and Senatore, Leonardo. IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/08/037.
Lewandowski, Matthew, & Senatore, Leonardo. IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence. United States. doi:10.1088/1475-7516/2017/08/037.
Lewandowski, Matthew, and Senatore, Leonardo. 2017. "IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence". United States. doi:10.1088/1475-7516/2017/08/037.
@article{osti_1394080,
title = {IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence},
author = {Lewandowski, Matthew and Senatore, Leonardo},
abstractNote = {Because large-scale structure surveys may very well be the next leading sources of cosmological information, it is important to have a precise understanding of the cosmological observables; for this reason, the Effective Field Theory of Large-Scale Structure (EFTofLSS) was developed. So far, most results in the EFTofLSS have used the so-called Einstein-de Sitter approximation, an approximation of the time dependence which is known to be accurate to better than one percent. However, in order to reach even higher accuracy, the full time dependence must be used. The computation with exact time dependence is sensitive to both infrared (IR) and ultraviolet (UV) effects in the loop integrands, and while these effects must cancel because of diffeomorphism invariance, they make numerical computation much less efficient. We provide a formulation of the one-loop, equal-time exact-time-dependence power spectrum of density perturbations which is manifestly free of these spurious IR and UV divergences at the level of the integrand. We extend our results to the total matter mode with clustering quintessence, show that IR and UV divergences cancel, and provide the associated IR- and UV-safe integrand. This also establishes that the consistency conditions are satisfied in this system. In conclusion, we then use our one-loop result to do an improved precision comparison of the two-loop dark-matter power spectrum with the Dark Sky N-body simulation.},
doi = {10.1088/1475-7516/2017/08/037},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2017,
place = {United States},
year = 2017,
month = 8
}

Journal Article:
Free Publicly Available Full Text
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