IRsafe and UVsafe integrands in the EFTofLSS with exact time dependence
Abstract
Because largescale 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 LargeScale Structure (EFTofLSS) was developed. So far, most results in the EFTofLSS have used the socalled Einsteinde 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 oneloop, equaltime exacttimedependence 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 UVsafe integrand. This also establishes that the consistency conditions are satisfied in this system. In conclusion, we then use our oneloopmore »
 Authors:
 Univ. Paris Saclay, GifsurYvette (France)
 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:
 AC0276SF00515
 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 14757516
 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. IRsafe and UVsafe integrands in the EFTofLSS with exact time dependence. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/08/037.
Lewandowski, Matthew, & Senatore, Leonardo. IRsafe and UVsafe integrands in the EFTofLSS with exact time dependence. United States. doi:10.1088/14757516/2017/08/037.
Lewandowski, Matthew, and Senatore, Leonardo. 2017.
"IRsafe and UVsafe integrands in the EFTofLSS with exact time dependence". United States.
doi:10.1088/14757516/2017/08/037.
@article{osti_1394080,
title = {IRsafe and UVsafe integrands in the EFTofLSS with exact time dependence},
author = {Lewandowski, Matthew and Senatore, Leonardo},
abstractNote = {Because largescale 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 LargeScale Structure (EFTofLSS) was developed. So far, most results in the EFTofLSS have used the socalled Einsteinde 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 oneloop, equaltime exacttimedependence 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 UVsafe integrand. This also establishes that the consistency conditions are satisfied in this system. In conclusion, we then use our oneloop result to do an improved precision comparison of the twoloop darkmatter power spectrum with the Dark Sky Nbody simulation.},
doi = {10.1088/14757516/2017/08/037},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2017,
place = {United States},
year = 2017,
month = 8
}

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