An effective description of dark matter and dark energy in the mildly nonlinear regime
Abstract
In the next few years, we are going to probe the lowredshift universe with unprecedented accuracy. Among the various fruits that this will bear, it will greatly improve our knowledge of the dynamics of dark energy, though for this there is a strong theoretical preference for a cosmological constant. We assume that dark energy is described by the socalled Effective Field Theory of Dark Energy, which assumes that dark energy is the Goldstone boson of time translations. Such a formalism makes it easy to ensure that our signatures are consistent with wellestablished principles of physics. Since most of the information resides at high wavenumbers, it is important to be able to make predictions at the highest wavenumber that is possible. Furthermore, the Effective Field Theory of LargeScale Structure (EFTofLSS) is a theoretical framework that has allowed us to make accurate predictions in the mildly nonlinear regime. In this paper, we derive the nonlinear equations that extend the EFTofLSS to include the effect of dark energy both on the matter fields and on the biased tracers. For the specific case of clustering quintessence, we then perturbatively solve to cubic order the resulting nonlinear equations and construct the oneloop power spectrum ofmore »
 Authors:
 Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States); Univ. Paris Saclay, GifsurYvette (France)
 Institute for Research in Fundamental Sciences (IPM), Tehran (Iran)
 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:
 1369465
 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: 05; Journal ID: ISSN 14757516
 Publisher:
 Institute of Physics (IOP)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTRONOMY AND ASTROPHYSICS; cosmological parameters from LSS; dark energy theory; dark matter theory; power spectrum
Citation Formats
Lewandowski, Matthew, Maleknejad, Azadeh, and Senatore, Leonardo. An effective description of dark matter and dark energy in the mildly nonlinear regime. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/05/038.
Lewandowski, Matthew, Maleknejad, Azadeh, & Senatore, Leonardo. An effective description of dark matter and dark energy in the mildly nonlinear regime. United States. doi:10.1088/14757516/2017/05/038.
Lewandowski, Matthew, Maleknejad, Azadeh, and Senatore, Leonardo. Thu .
"An effective description of dark matter and dark energy in the mildly nonlinear regime". United States.
doi:10.1088/14757516/2017/05/038. https://www.osti.gov/servlets/purl/1369465.
@article{osti_1369465,
title = {An effective description of dark matter and dark energy in the mildly nonlinear regime},
author = {Lewandowski, Matthew and Maleknejad, Azadeh and Senatore, Leonardo},
abstractNote = {In the next few years, we are going to probe the lowredshift universe with unprecedented accuracy. Among the various fruits that this will bear, it will greatly improve our knowledge of the dynamics of dark energy, though for this there is a strong theoretical preference for a cosmological constant. We assume that dark energy is described by the socalled Effective Field Theory of Dark Energy, which assumes that dark energy is the Goldstone boson of time translations. Such a formalism makes it easy to ensure that our signatures are consistent with wellestablished principles of physics. Since most of the information resides at high wavenumbers, it is important to be able to make predictions at the highest wavenumber that is possible. Furthermore, the Effective Field Theory of LargeScale Structure (EFTofLSS) is a theoretical framework that has allowed us to make accurate predictions in the mildly nonlinear regime. In this paper, we derive the nonlinear equations that extend the EFTofLSS to include the effect of dark energy both on the matter fields and on the biased tracers. For the specific case of clustering quintessence, we then perturbatively solve to cubic order the resulting nonlinear equations and construct the oneloop power spectrum of the total density contrast.},
doi = {10.1088/14757516/2017/05/038},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2017,
place = {United States},
year = {Thu May 18 00:00:00 EDT 2017},
month = {Thu May 18 00:00:00 EDT 2017}
}
Web of Science

In the next few years, we are going to probe the lowredshift universe with unprecedented accuracy. Among the various fruits that this will bear, it will greatly improve our knowledge of the dynamics of dark energy, though for this there is a strong theoretical preference for a cosmological constant. We assume that dark energy is described by the socalled Effective Field Theory of Dark Energy, which assumes that dark energy is the Goldstone boson of time translations. Such a formalism makes it easy to ensure that our signatures are consistent with wellestablished principles of physics. Since most of the informationmore »

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