2017/01/31 by Matthew Lewandowski, Leonardo Senatore
Physics and Astronomy · #Algorithm #Astronomy and Astrophysical Research #Astrophysics #Computation #Cosmological perturbation theory #Cosmology #Cosmology and Gravitation Theories #Dark energy #Dark matter #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Matter power spectrum #Observable #Physics #Quantum mechanics #Spectral density #Spurious relationship #Statistical physics #Theoretical physics #astro-ph.CO
paper · pdf · doi:10.1088/1475-7516/2017/08/037
33 pages, 7 figures, code available at http://web.stanford.edu/~senatore/ ; version published in JCAP, minor corrections
openalex publication_date 2017/08/31 · arxiv created 2017/09/12 · arxiv updated 2017/09/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
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. 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.