Inferring $S_8(z)$ and $\gamma (z)$ with cosmic growth rate measurements using machine learning

Abstract

Measurements of the cosmological parameter $S_8$ provided by cosmic microwave background and large scale structure data reveal some tension between them, suggesting that the clustering features of matter in these early and late cosmological tracers could be different. In this work, we use a supervised learning method designed to solve Bayesian approach to regression, known as Gaussian Processes regression, to quantify the cosmic evolution of $S_8$ up to $z\sim 1.5$. For this, we propose a novel approach to find firstly the evolution of the function ${\sigma }_8(z)$, then we find the function $S_8(z)$. As a sub-product we obtain a minimal cosmological model-dependent ${\sigma }_8(z=0)$ and $S_8(z=0)$ estimates. We select independent data measurements of the growth rate $f(z)$ and of $[f{\sigma }_8](z)$ according to criteria of non-correlated data, then we perform the Gaussian reconstruction of these data sets to obtain the cosmic evolution of ${\sigma }_8(z)$, $S_8(z)$, and the growth index $\gamma (z)$. Our statistical analyses show that $S_8(z)$ is compatible with Planck $\Lambda$CDM cosmology; when evaluated at the present time we find ${\sigma }_8(z=0)=0.766\pm 0.116$ and $S_8(z=0)=0.732\pm 0.115$. Applying our methodology to the growth index, we find $\gamma (z=0)=0.465\pm 0.140$. Moreover, we compare our results with others recently obtained in the literature. In none of these functions, i.e. ${\sigma }_8(z)$, $S_8(z)$, and $\gamma (z)$, do we find significant deviations from the standard cosmology predictions.

8 pages and 10 figures. Accepted for publication in EPJC

References in corpus (32)

• Cosmological Constraints from the SDSS Luminous Red Galaxies
• Two new diagnostics of dark energy
• A test of the nature of cosmic acceleration using galaxy redshift distortions
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the luminous red galaxy sample from the anisotropic correlation function between redshifts 0.6 and 1
• KiDS-450 + 2dFLenS: Cosmological parameter constraints from weak gravitational lensing tomography and overlapping redshift-space galaxy clustering
• Gaussian Process Cosmography
• The 2dF-SDSS LRG and QSO Survey: QSO clustering and the L-z degeneracy
• The 2dF-SDSS LRG and QSO Survey: The LRG 2-Point Correlation Function and Redshift-Space Distortions
• Arbitrating the $S_8$ discrepancy with growth rate measurements from Redshift-Space Distortions
• Non-parametric spatial curvature inference using late-universe cosmological probes
• Joint analysis of 6dFGS and SDSS peculiar velocities for the growth rate of cosmic structure and tests of gravity
• Beyond BAO: improving cosmological constraints from BOSS with measurement of the void-galaxy cross-correlation
• Growth rate of cosmological perturbations at z ~ 0.1 from a new observational test
• Hubble tension or a transition of the Cepheid SnIa calibrator parameters?
• The growth of density perturbations in the last $\sim$10 billion years from tomographic large-scale structure data
• Late time approaches to the Hubble tension deforming $H(z)$, worsen the growth tension
• Measurements of $H_0$ and reconstruction of the dark energy properties from a model-independent joint analysis
• BAO angular scale at z_eff = 0.11 with the SDSS blue galaxies
• Constraining neutrino mass with weak lensing Minkowski Functionals
• Measuring the growth rate of structure with Type IA Supernovae from LSST
• The growth rate of cosmic structures in the local Universe with the ALFALFA survey
• Optimising growth of structure constraints on modified gravity
• Model-independent constraints on ${\Omega }_m$ and $H(z)$ from the link between geometry and growth
• Baryon acoustic oscillations signature in the three-point angular correlation function from the SDSS-DR12 quasar survey
• The angular scale of homogeneity in the Local Universe with the SDSS blue galaxies
• Non-parametric reconstruction of interaction in the cosmic dark sector
• The homogeneity scale and the growth rate of cosmic structures
• Observational constraints on Starobinsky $f(R)$ cosmology from cosmic expansion and structure growth data
• Multi-tasking the growth of cosmological structures
• Reconstruction of cosmological matter perturbations in Modified Gravity
• Elucidating cosmological model dependence with $H_0$
• Testing homogeneity of the galaxy distribution in the SDSS using Renyi entropy

Cited by in corpus (27)

• The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
• Nonparametric late-time expansion history reconstruction and implications for the Hubble tension in light of recent DESI and type Ia supernovae data
• Quantifying the $S_8$ tension and evidence for interacting dark energy from redshift-space distortion measurements
• Cosmographic view on the $H_0$ and ${\sigma }_8$ tensions
• Exploring new physics in the late Universe's expansion through non-parametric inference
• $\Lambda$CDM is alive and well
• Improved null tests of $\Lambda$CDM and FLRW in light of DESI DR2
• Gaussian-process reconstructions and model building of quintom dark energy from latest cosmological observations
• Analytical Gaussian Process Cosmography: Unveiling Insights into Matter-Energy Density Parameter at Present
• Linear matter density perturbations in the ${\Lambda }_{\mathrm{s}}$CDM model: Examining growth dynamics and addressing the $S_8$ tension
• The cosmology of $f(R,L_m)$ gravity: constraining the background and perturbed dynamics
• The bulk flow motion and the Hubble-Lema\^ıtre law in the Local Universe with the ALFALFA survey
• Reconstructing the growth index $\gamma$ with Gaussian Processes
• Constraining viscous fluid models in $f(Q)$ gravity with data
• Measuring the matter fluctuations in the Local Universe with the ALFALFA catalog
• A comprehensive data-driven odyssey to explore the equation of state of dark energy
• Is ${\omega }_0{\omega }_a$CDM a good model for the clumpy Universe?
• Cosmological constraints on $R^2$-corrected Appleby-Battye model
• Testing time-delayed cosmology
• Cosmic curvature on large-scale structures with homogeneous dark energy
• Probing the Cosmic Distance Duality Relation via Non-Parametric Reconstruction for High Redshifts
• Viability of general relativity and modified gravity cosmologies using high-redshift cosmic probes
• Revisiting the temperature evolution law of the CMB with gaussian processes
• Scalar perturbation and density contrast evolution in $f(Q,C)$ gravity
• Structure formation in a non-canonical scalar field model of clustering dark energy
• A model-independent test of speed of light variability with cosmological observations
• Testing the growth of cosmic structures during the Dark Ages