Related papers: Early Cosmology Constrained
A key assumption of the standard cosmological model is that the temperature of the cosmic microwave background (CMB) radiation scales with cosmological redshift $z$ as $T_{\rm CMB}(z) \propto (1+z)$ at all times after recombination at…
The statistical uncertainty in measuring the primordial density perturbations on a given comoving scale is dictated by the number of independent regions of that scale that are accessible to an observer. This number varies with cosmic time…
We present the first comprehensive discussion of constraints on the cosmic neutrino background (C$\nu$B) overdensity, including theoretical, experimental and cosmological limits for a wide range of neutrino masses and temperatures.…
A precise measurement of the curvature of the Universe is of primeval importance for cosmology since it could not only confirm the paradigm of primordial inflation but also help in discriminating between different early Universe scenarios.…
Constraints on the main cosmological parameters using CMB or large scale structure data are usually based on power-law assumption of the primordial power spectrum (PPS). However, in the absence of a preferred model for the early universe,…
We derive constraints on cosmological parameters using the power spectrum of galaxy clustering measured from the final two-degree field galaxy redshift survey (2dFGRS) and a compilation of measurements of the temperature power spectrum and…
This paper derives an upper limit on the density $\rho_{\scriptstyle\Lambda}$ of dark energy based on the requirement that cosmological structure forms before being frozen out by the eventual acceleration of the universe. By allowing for…
Recent cosmological observations, such as the measurement of the primordial 4He abundance, CMB, and large scale structure, give preference to the existence of extra radiation component, Delta N_nu > 0. The extra radiation may be accounted…
In the paper, we consider two models in which dark energy is coupled with either dust matter or dark matter, and discuss the conditions that allow more time for structure formation to take place at high redshifts. These models are expected…
We reconstruct the shape of the primordial power spectrum of curvature perturbations in extended cosmological models, including addition of massive neutrinos, extra relativistic species or varying primordial helium abundance, from the…
Driven by the CMB temperature-redshift ($T$-$z$) relation as demanded by deconfining SU(2) Yang-Mills thermodynamics, an according cosmological model is proposed and analysed. This model -- SU(2)$_\CMB$ -- exhibits a dark sector,…
Minimal atomic dark matter with its distinctive cooling mechanisms offers an instructive framework for understanding the potential impact of dark matter on small-scale structure formation and early cosmology. The model consists of two…
We discuss the cosmological degeneracy between the Hubble parameter H(z), the age of the universe and cosmological parameters describing simple variations from the minimal LCDM model. We show that independent determinations of the Hubble…
We investigate the effect of potentially large distortions of the relic neutrino spectra on cosmological observables. To that end, we consider a phenomenological model of "gray" spectral distributions, described by a single parameter, which…
We use observational data on the large scale structure (LSS) of the Universe measured over a wide range of scales from sub-galactic up to horizon scale and on the cosmic microwave background anisotropies to determine cosmological parameters…
Cosmology has entered an era of unprecedented precision, yet increasing accuracy has revealed cracks in the standard $\Lambda$CDM paradigm. Although the model remains highly successful when confronted with individual datasets, joint…
The combination of detections of anisotropy in the Cosmic Microwave Background radiation and observations of the large-scale distribution of galaxies probes the primordial density fluctuations of the universe on spatial scales varying by…
We use large-scale cosmological observations to place constraints on the dark-matter pressure, sound speed and viscosity, and infer a limit on the mass of warm-dark-matter particles. Measurements of the cosmic microwave background (CMB)…
When combining cosmological and oscillations results to constrain the neutrino sector, the question of the propagation of systematic uncertainties is often raised. We address this issue in the context of the derivation of an upper bound on…
Cosmological theories for the origin and evolution of structure in the Universe are highly predictive of the form of the angular power spectrum of cosmic microwave background fluctuations. We present new results from a comprehensive study…