We present limits on the parameters of the oΛCDM, w0 CDM, and w0wa CDM models obtained from the joint analysis of the full-shape, baryon acoustic oscillations (BAO), big bang nucleosynthesis (BBN) ...and supernovae data. Our limits are fully independent of the data on the cosmic microwave background (CMB) anisotropies, but rival the CMB constraints in terms of parameter error bars. We find the spatial curvature consistent with a flat universe Ωk=−0.043−0.036+0.036 (68% C.L.); the dark-energy equation of state parameter w0 is measured to be w0 =−1.031−0.048+0.052 (68% C.L.), consistent with a cosmological constant. This conclusion also holds for the time-varying dark energy equation of state, for which we find w0 =−0.98−0.11+0.099 and wa =−0.33−0.48+0.63 (both at 68% C.L.). The exclusion of the supernovae data from the analysis does not significantly weaken our bounds. This shows that using a single external BBN prior, the full-shape and BAO data can provide strong CMB-independent constraints on the nonminimal cosmological models.
We present a new open-source code that calculates one-loop power spectra and cross spectra for matter fields and biased tracers in real and redshift space. These spectra incorporate all ingredients ...required for a direct application to data: nonlinear bias and redshift-space distortions, infrared resummation, counterterms, and the Alcock-Paczynski effect. Our code is based on the Boltzmann solver class and inherits its advantageous properties: user friendliness, ease of modification, high speed, and simple interface with other software. We present detailed descriptions of the theoretical model, the code structure, approximations, and accuracy tests. A typical end-to-end run for one cosmology takes 0.3 seconds, which is sufficient for Markov chain Monte Carlo parameter extraction. As an example, we apply the code to the Baryon Oscillation Spectroscopic Survey (BOSS) data and infer cosmological parameters from the shape of the galaxy power spectrum.
We study production of keV scale sterile neutrinos with large mixing with the Standard Model sector 1. Conventional mechanism of sterile neutrino generation in the early Universe leads to ...overproduction of the Dark Matter and strong X-ray signal from sterile neutrino decay. It makes anticipated groundbased experiments on direct searches of sterile-active mixing unfeasible. We argue that for models with a hidden sector coupled to the sterile neutrinos cosmological and astrophysical constraints can be significantly alleviated. In developed scenario a phase transition in the hidden sector modifies the standard oscillation picture and leads to significantly larger mixing angles, thus opening new perspectives for future neutrino experiments such as Troitsk
v
-mass and KATRIN.
This work was made in collaboration with Fedor Bezrukov and Dmitry Gorbunov.
A promising idea to resolve the long standing Hubble tension is to postulate a new subdominant dark-energy-like component in the prerecombination Universe which is traditionally termed as the early ...dark energy (EDE). However, as shown in the Refs. J. C. Hill et al., Early dark energy does not restore cosmological concordance, Phys. Rev. D 102, 043507 (2020), M. M. Ivanov et al.,Constraining early dark energy with large-scale structure, Phys. Rev. D 102, 103502 (2020). the cosmic microwave background (CMB) and large-scale structure (LSS) data impose tight constraints on this proposal. Here, we revisit these strong bounds considering the Planck CMB temperature anisotropy data at large angular scales and the SPTPol polarization and lensing measurements. As advocated in A. Chudaykin et al., Combined analysis of Planck and SPTPol data favors the early dark energy models, J. Cosmol. Astropart. Phys. 08 (2020) 013. another paper, this combined data approach predicts the CMB lensing effect consistent with the Λ CDM expectation and allows one to efficiently probe both large and small angular scales. Combining Planck and SPTPol CMB data with the full-shape BOSS likelihood and information from photometric LSS surveys in the EDE analysis we found for the Hubble constant H0 = 69.79 ± 0.99 km s−1 Mpc−1 and for the EDE fraction fEDE < 0.094 (2σ). These bounds obtained without including a local distance ladder measurement of H0 (SH0ES) alleviate the Hubble tension to a 2.5 σ level. Including further the SH0ES data we obtain H0 = 71.81 ± 1.19 km s−1 Mpc−1 and fEDE = 0.088 ± 0.034 in full accordance with SH0ES. We also found that a higher value of H0 does not significantly deteriorate the fit to the LSS data. Overall, the EDE scenario is (though weakly) favored over Λ CDM even after accounting for unconstrained directions in the cosmological parameter space. We conclude that the large-scale Planck temperature and SPTPol polarization measurements along with LSS data do not rule out the EDE model as a resolution of the Hubble tension. This paper underlines the importance of the CMB lensing effect for robust constraints on the EDE scenario.
An important aspect of large-scale structure data analysis is the presence of non-negligible theoretical uncertainties, which become increasingly important on small scales. We show how to incorporate ...these uncertainties in realistic power spectrum likelihoods by an appropriate change of the fitting model and the covariance matrix. The inclusion of the theoretical error has several advantages over the standard practice of using the sharp momentum cut kmax. First, the theoretical error covariance gradually suppresses the information from the short scales as the employed theoretical model becomes less reliable. This allows one to avoid laborious measurements of kmax, which is an essential part of the standard methods. Second, the theoretical error likelihood gives unbiased constraints with reliable error bars that are not artificially shrunk due to overfitting. In realistic settings, the theoretical error likelihood yields essentially the same parameter constraints as the standard analysis with an appropriately selected kmax, thereby effectively optimizing the choice of k max . We demonstrate these points using the large-volume N-body data for the clustering of matter and galaxies in real and redshift space. In passing, we validate the effective field theory description of the redshift space distortions and show that the use of the one-parameter phenomenological Gaussian damping model for fingers-of-God causes significant biases in parameter recovery.
Cosmology intertwined III: fσ8 and S8 Di Valentino, Eleonora; Anchordoqui, Luis A.; Akarsu, Özgür ...
Astroparticle physics,
September 2021, Volume:
131
Journal Article
Peer reviewed
The standard Λ Cold Dark Matter cosmological model provides a wonderful fit to current cosmological data, but a few statistically significant tensions and anomalies were found in the latest data ...analyses. While these anomalies could be due to the presence of systematic errors in the experiments, they could also indicate the need for new physics beyond the standard model. In this Letter of Interest we focus on the tension between Planck data and weak lensing measurements and redshift surveys, in the value of the matter energy density Ωm and the amplitude σ8 (or the growth rate fσ8) of cosmic structure. We list a few promising models for solving this tension, and discuss the importance of trying to fit multiple cosmological datasets with complete physical models, rather than fitting individual datasets with a few handpicked theoretical parameters.
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