Blinded challenge for precision cosmology with large-scale structure: Results from effective field theory for the redshift-space galaxy power spectrum

Full-shape cosmology analysis of SDSS-III BOSS galaxy power spectrum using emulator-based halo model: a $5\%$ determination of $σ_8$

“…While these perturbation theorybased templates give useful predictions at linear and quasi-nonlinear scales up to k ∼ 0.2 h Mpc −1 , application of these models to even smaller scales is still disturbed by even higher-order contributions of both the density and velocity fields as well as non-perturbative effects arising from the dynamics beyond shell crossing, i.e., formation of galaxies (or dark matter halos) [e.g., [28][29][30][31][32][33][34]. Consequently, the cosmological analysis of the galaxy power spectrum has been typically limited to the wave number k 0.15 -0.2 h Mpc −1 , depending on the redshift and the accuracy of the model required to meet the statistical precision of data [24,25,35]. In other words, the clustering information on the higher-k scales does not seem practical for cosmology in this method, because the information is used to basically constrain higher-order bias parameters and other nuisance parameters that need to be introduced for the theoretical consistency of models.…”

The effective field theory of large-scale structures and multiple tracers

“…is limited to narrow band around the BAO signature. See [22] for a joint analysis using only FS and BAO, without CMB, and, for instance, [23,24,25,26,27,28] for other FS procedures. Thus, we can affirm that:…”

“…On the right, the dimensionless power spectrum for each tracer, defined in Eq. (5.15) by splitting the tracers into multiple distinct populations 27 . We also display in the same figure the cross-power spectrum (AB), as well as the auto-power spectrum of the combined halos (A + B).…”

Statistical and Numerical Methods for Precision Cosmology

“…Analyzing this data will not be an easy job: the mere task of processing it will be challenging, pushing for the development of more efficient analysis algorithms; current theoretical models are not accurate enough for the analysis of this data, especially at the smallest scales (Nishimichi et al, 2020), and finally, it is also very important to improve on statistical methods to extract as much information as possible from the measurements.…”

“…The number of available Fourier modes grows with k, and therefore, non-linear scales contain, in principle, a vast amount of information. Predictions of the power spectrum using Standard Perturbation Theory (hereafter SPT) quickly break down as we leave the linear regime, at around k ≈ 0.1h/Mpc (Bernardeau et al, 2002), and even with the great effort of developing an Effective Field Theory of Large Scale Structure, the theoretical predictions still reach only modest scales k ≈ 0.2h/Mpc (Carrasco, Hertzberg, and Senatore, 2012;Nishimichi et al, 2020). Recent works have been taking another route, using different computational methods (e.g.…”