Related papers: Large Scale Structure as a Probe of Gravitational …
We consider a test of the Copernican Principle through observations of the large-scale structures, and for this purpose we study the self-gravitating system in a relativistic huge void universe model which does not invoke the Copernican…
The theoretical and observational consequences of thermodynamics of open systems, which allow particle creation are investigated in modified $f(R,T)$ ($R$ is the Ricci scalar and $T$ is the trace of energy-momentum tensor) theory of gravity…
We investigate the global texture model of structure formation in cosmogonies with non-zero cosmological constant for different values of the Hubble parameter. We find that the absence of significant acoustic peaks and little power on large…
We discuss the construction of cosmological models within the framework of Macroscopic Gravity (MG), which is a theory that models the effects of averaging the geometry of space-time on large scales. We find new exact spatially homogeneous…
Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data confirm the ellipticity of anisotropies of Cosmic Microwave Background (CMB) maps, found previously for Boomerang and WMAP 1-year high sensitivity maps. The low noise level of the WMAP…
The evolution of cosmological large-scale perturbations is described in terms of the concordant model based on the recent discovery of cosmic vacuum. It is demonstrated that the process is robustly controlled by a few epoch-independent…
Scale-dependent gravity is an extension of general relativity in which the Newton and cosmological constants may vary slightly with the energy scale due to remnant low-energy quantum effects. A fundamental feature of this approach is the…
The effect of gravitational lensing on cosmic microwave background (CMB) anisotropies is investigated using the power spectrum approach. The lensing effect can be calculated in any cosmological model by specifying the evolution of…
The dynamics of expansion and large scale structure formation of the Universe are analyzed for models with dark energy in the form of a phantom scalar field which initially mimics a $\Lambda$-term and evolves slowly to the Big Rip…
With the increasing wealth of high-quality astronomical and cosmological data and the manifold departures from General Relativity in principle conceivable, the development of generalized parametrization frameworks that unify gravitational…
Modified gravity can be considered as an alternative to dark energy. In a generalized theory of gravity, the universe may accelerate while containing only baryonic and dark matter. We study, in particular, the evolution of matter…
In this work we study the cosmology of the general f(T) gravity theory. We express the modified Einstein equations using covariant quantities, and derive the gauge-invariant perturbation equations in covariant form. We consider a specific…
Cosmology in extended theories of gravity is considered assuming the Palatini variational principle, for which the metric and connection are independent variables. The field equations are derived to linear order in perturbations about the…
Deviations from general relativity, such as could be responsible for the cosmic acceleration, would influence the growth of large scale structure and the deflection of light by that structure. We clarify the relations between several…
New measurements of galaxy clustering and background radiations provide improved constraints on the isotropy and homogeneity of the Universe on large scales. In particular, the angular distribution of radio sources and the X-Ray Background…
One way to account for the acceleration of the universe is to modify general relativity, rather than introducing dark energy. Typically, such modifications introduce new degrees of freedom. It is interesting to consider models with no new…
The ghost-free theory of massive gravity with two dynamical metrics has been shown to produce viable cosmological expansion, where the late-time acceleration of the Universe is due to the finite range of the gravitational interaction rather…
These lectures deal with our current knowledge of the matter distribution in the universe, focusing on how this is studied via the large-scale structure seen in galaxy surveys. We first assemble the necessary basics needed to understand the…
Anisotropies in the cosmic microwave background radiation due to gravity waves are investigated. An initial spectrum of gravity waves may have been induced during an epoch of inflation. We study the propagation of such a spectrum in a…
Long-wavelength gravitational waves can induce significant temperature anisotropy in the cosmic microwave background. Distinguishing this from anisotropy induced by energy density fluctuations is critical for testing inflationary cosmology…