Related papers: Redshift drift cosmography for model-independent c…
We study non-viscous and viscous holographic dark energy models for a homogeneous and isotropic flat Friedmann-Robertson-Walker Universe in $f(R,T)$ gravity. We find that the Hubble horizon as an IR cut-off is suitable for both the models…
A leading way to constrain physical theories from cosmological observations is to test their predictions for the angular clustering statistics of matter tracers, a technique that is set to become ever more central with the next generation…
Knowing the late time evolution of the Universe and finding out the causes for this evolution are the important challenges of modern cosmology. In this work, we adopt a model-independent cosmographic approach and approximate the Hubble…
Nearly a century after the discovery that we live in an expanding Universe, and two decades after the discovery of accelerating cosmic expansion, there remains no direct detection of this acceleration via redshift drift - a change in the…
The dipole anisotropy induced by our peculiar motion in the sky distribution of cosmologically distant sources is an important consistency test of the standard FLRW cosmology. In this work, we formalize how to compute the kinematic matter…
The standard $\Lambda$CDM cosmological model faces increasing tensions between key observations, motivating tests that probe its underlying assumptions. In a companion letter, we present a model-independent framework that combines…
We reverse the logic behind the apparent existence of $H_0$-tension, to design diagnostics for cosmological models. The basic idea is that the non-constancy of $H_0$ inferred from observations at different redshifts is a null hypothesis…
In this research paper, we explore a well-motivated parametrization of the time-dependent deceleration parameter, characterized by a cubic form, within the context of late time cosmic acceleration. The current analysis is based on the…
We propose a model universe in the matter dominated phase described by a FRW background with local inhomogeneities, like our local patch, grown out of the primordial fluctuations. Our sub-horizon local patch consisting of different…
A generalized model of space-time is given, taking into consideration the anisotropic structure of fields which are depended on the position and the direction (velocity).In this framework a generalized FRW-metric the Raychaudhouri and…
The homogeneous, isotropic, and flat $\Lambda$CDM universe favored by observations of the cosmic microwave background can be described using only Euclidean geometry, locally correct Newtonian mechanics, and the basic postulates of special…
Cosmological consequences of the nonsymmetric gravitational theory (NGT) are studied. The structure of the NGT field equations is analyzed for an inhomogeneous and anisotropic universe, based on the spherically symmetric field equations. It…
For known gravitational lens systems the redshift distribution of the lenses is compared with theoretical expectations for $10^{4}$~Friedmann-Lema\^\i tre~cosmological models, which more than cover the range of possible cases. The…
The extension of the so-called "empty" (with gravity and antigravity that compensate each other in full or do not exist at all) universe and cosmological redshift in it are considered in this paper. Its flat space-time can be submitted not…
We study cosmological constraints on the various accelerating models of the universe using the time evolution of the cosmological redshift of distant sources. The important characteristic of this test is that it directly probes the…
We compute the red and blue shifts for astrophysical and cosmological sources. In particular, we consider low, intermediate and high gravitational energy domains. Thereby, we handle the binary system Earth - Mars as low energy landscape…
A recently proposed Asymptotically Safe cosmology provides an elegant mechanism towards understanding the nature of dark energy and its associated cosmic coincidence problem. The underlying idea is that the accelerated expansion of the…
The minimal requirement for cosmography - a nondynamical description of the universe - is a prescription for calculating null geodesics, and timelike geodesics as a function of their proper time. In this paper, we consider the most general…
The geometry of the Universe may be probed using the Alcock-Paczynski (AP) effect, in which the observed redshift size of a spherical distribution of sources relative to its angular size varies according to the assumed cosmological model.…
We investigate the evolution of a spatially flat Friedmann-Robertson-Walker (FRW) universe in the framework of scalar non-metricity theory of gravity. In the model, we consider dark matter (DM) and dark energy (DE) described by the scalar…