Related papers: Bounds on the basic physical parameters for anisot…
The Cosmological Principle posits that the Universe is isotropic on the largest scales. While widely supported, this foundational assumption remains testable. We analyse the angular distribution of over one million quasars from the…
For a wide class of self-gravitating systems, we show that if the density is cusped like 1/r^{gamma} near the center, then the limiting value of the anisotropy parameter beta = 1 - <v_T^2>/(2<v_r^2>) at the center may not be greater than…
Observational constraints guide one forcefully to examine models in which the matter density is substantially less than critical density. Particularly noteworthy are those which are consistent with inflation. For these models, microwave…
The observational evidence regarding the present cosmological aspects tells us about the presence of very little anisotropy in the universe on a large scale. Here, in this paper, we attempt to study locally rotationally symmetric (LRS)…
Non-radial oscillation modes of neutron stars serve as diagnostics of their internal composition and relativistic structure. In this work, we investigate the perturbations of static and spherically symmetric neutron stars characterized by…
We investigate the stability of self-gravitating spherically symmetric anisotropic spheres under radial perturbations. We consider both the Newtonian and the full general-relativistic perturbation treatment. In the general-relativistic…
We present a spherically symmetric solution of the general relativistic field equations in isotropic coordinates for charged fluid with pressure anisotropy, compatible with a super dense star modeling. Further, we have constructed an…
We present an anisotropic cosmological model based on a new exact solution of Einstein equations. The matter content consists of an anisotropic scalar field minimally coupled to gravity and of two isotropic perfect fluids that represent…
We set up in detail the general formalism to model polytropic general relativistic stars with anisotropic pressure. We shall consider two different possible polytropic equations, all of which yield the same Lane-Emden equation in the…
We investigate various anisotropic spherical distributions of charged celestial bodies within the context of f(R) gravity, where R represents the Ricci scalar. The properties of specific charged compact objects are analyzed by using the…
The analysis of axisymmetric spacetimes, dynamical or stationary, is usually made in the reduced space. We prove here a stability property of the quo- tient space and use it together with minimal surface techniques to constraint the shape…
Extensive, accurate imaging of the Cosmic Background Radiation temperature anisotropy at sub--degree angular resolution is widely recognized as one of the most crucial goals for cosmology and astroparticle physics in the next decade. We…
We build slowly rotating anisotropic neutron stars using the Hartle-Thorne formalism, employing three distinct anisotropy models--Horvat, Bowers-Liang, and a covariant model--to characterize the relationship between radial and tangential…
Cosmic rays in the energy range from about 10's GeV to several 100's TeV are observed on Earth with an energy-dependent anisotropy of order 0.01-0.1%, and a consistent topology that appears to significantly change at higher energy. The…
We consider the benefits of measuring cosmic statistical anisotropy from redshift-space correlators of the galaxy number density fluctuation and the peculiar velocity field without adopting the plane-parallel (PP) approximation. Since the…
This article presents a new model for anisotropic compact stars that are confined to physical dark matter in the background of $f(T)$ teleparallel gravity. The model is based on the equation of state (EoS) of the bag model type and the…
We discuss the threshold anomaly in ultra-high energy cosmic ray physics by assuming that the matter world just be perturbation of a de Sitter universe, which is consistent with the recent astronomical observations: about two thirds of the…
We investigate cosmologies where the accelerated expansion of the Universe is driven by a field with an anisotropic equation of state. We model such scenarios within the Bianchi I framework, introducing two skewness parameters to quantify…
The present paper is devoted to a study of the equilibrium configurations of slowly rotating anisotropic stars in the framework of general relativity. For that purpose, we provide the equations of structure where the rotation is treated to…
The present paper is devoted to investigate the possible emergence of relativistic compact stellar objects through modified $f(R,T)$ gravity. For anisotropic matter distribution, we used Krori and Barura solutions and two notable and viable…