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Related papers: Modelling Inhomogeneity in Szekeres Spacetime

200 papers

This thesis investigates the evolution of galaxies in diverse environments, utilizing Sloan Digital Sky Survey (SDSS) data to explore the impact of environmental richness on central and satellite galaxies across stellar mass ranges,…

Astrophysics of Galaxies · Physics 2025-03-14 V. M. Sampaio

The ratio eta/s, shear viscosity (eta) to entropy density (s), reaches its local minimum at the (second order) phase transition temperature in a wide class of systems. It was suspected that this behavior might be universal. However, a…

High Energy Physics - Phenomenology · Physics 2011-06-28 Jiunn-Wei Chen , Chang-Tse Hsieh , Han-Hsin Lin

We lay out a general framework for calculating the variation of a set of cosmological observables, down the past null cone of an arbitrarily placed observer, in a given arbitrary inhomogeneous metric. The observables include redshift,…

General Relativity and Quantum Cosmology · Physics 2018-02-21 Charles Hellaby , Anthony Walters

We study, for the first time, how shear and angular momentum modify typical parameters of the spherical collapse model, in dark energy dominated universes. In particular, we study the linear density threshold for collapse…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 A. Del Popolo , F. Pace , J. A. S. Lima

In this paper, we analyze the behavior of statistical complexity in several systems where two identical densities that travel in opposite direction cross each other. Besides the crossing between two Gaussian, rectangular and triangular…

Pattern Formation and Solitons · Physics 2010-06-30 Ricardo Lopez-Ruiz , Jaime Sanudo

Particle number violating interactions wash out the primordial asymmetry of particle number density generated by some interaction satisfying Sakharov conditions for baryogenesis. In this paper, we study how the primordial asymmetry evolves…

High Energy Physics - Phenomenology · Physics 2014-07-23 Ryuichi Hotta , Takuya Morozumi , Hiroyuki Takata

We investigate the conditions under which cosmological variations in physical `constants' and scalar fields are detectable on the surface of local gravitationally-bound systems, such as planets, in non-spherically symmetric background…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Douglas J. Shaw , John D. Barrow

Effects of inhomogeneities on observations have been vastly studied using both perturbative methods, N-body simulations and Swiss cheese solutions to the Einstein equations. In nearly all cases, such studied setups assume vanishing spatial…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-30 S. M. Koksbang

As evidenced by a great number of works, it is common practice to assume that the Universe is flat. However, the majority of studies which make use of observational data to constrain the curvature density parameter are premised on the…

General Relativity and Quantum Cosmology · Physics 2019-07-18 Christine R. Farrugia , Joseph Sultana

This paper presents the cosmological applications of the quasispherical Szekeres model. The quasispherical Szekeres model is an exact solution of the Einstein field equations, which represents a time-dependent mass dipole superposed on a…

Astrophysics · Physics 2007-05-23 Krzysztof Bolejko

We analyse the universe homogeneously filled up by different dark energies. We calculate the relations between time and the scale factor. We thoroughly check the differences to be obtained with the changes of different parameters. $t$ vs…

General Relativity and Quantum Cosmology · Physics 2018-07-26 Promila Biswas , Ritabrata Biswas

We reconsider the issue of proving large scale spatial homogeneity of the universe, given isotropic observations about us and the possibility of source evolution both in numbers and luminosities. Two theorems make precise the freedom…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Nazeem Mustapha , Charles Hellaby , G. F. R. Ellis

We propose a dynamic Kerr effect experiment for the distinction between dynamic heterogeneous and homogeneous relaxation in glassy systems. The possibility of this distinction is due to the inherent nonlinearity of the Kerr effect signal.…

Soft Condensed Matter · Physics 2009-11-11 Uli Haeberle , Gregor Diezemann

Holographic duality is a powerful tool to investigate the far-from equilibrium dynamics of superfluids and other phases of quantum matter. For technical reasons it is usually assumed that, after a quench, the far-from equilibrium fields are…

High Energy Physics - Theory · Physics 2015-06-17 Antonio M. García-García , Hua Bi Zeng , Hai Qing Zhang

Dense cores inherit turbulent motions from the interstellar medium in which they form. As a tool for comparison to both simulations and observations, it is valuable to construct theoretical core models that can relate their internal density…

Astrophysics of Galaxies · Physics 2025-06-05 Sanghyuk Moon , Eve C. Ostriker

We use cosmological N-body simulations to investigate whether measurements of the moments of large-scale structure can yield constraints on primordial non-Gaussianity. We measure the variance, skewness, and kurtosis of the evolved density…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-24 Qingqing Mao , Andreas A. Berlind , Cameron K. McBride , Robert J. Scherrer , Roman Scoccimarro , Marc Manera

We investigate the non-linear evolution of spherical density and velocity perturbations of dark matter and dark energy in the expanding Universe. For that we have used the conservation and Einstein equations to describe the evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-04 M. Tsizh , B. Novosyadlyj

This comment contains a suggestion for a slight modification of Israel's covariant formulation of junction conditions between two spacetimes, placing both sides on equal footing with normals having uniquely defined orientations. The signs…

General Relativity and Quantum Cosmology · Physics 2010-04-06 D. S. Goldwirth , J. Katz

We investigate the anisotropic evolution of spacetime driven by perfect fluid with off-diagonal shear-viscosity components. We consider the simplest form of the equation of state for fluid, for which the pressure and the shear stress are…

General Relativity and Quantum Cosmology · Physics 2023-12-25 Inyong Cho , Rajibul Shaikh

We revisit how super-Hubble cosmological fluctuations induce, at any time in the cosmic history, a non-vanishing spatial curvature of the local background metric. The random nature of these fluctuations promotes the curvature density…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-06 Baptiste Blachier , Pierre Auclair , Christophe Ringeval , Vincent Vennin