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Related papers: Cosmological modelling with Regge calculus

200 papers

The exact Friedman solution to the field equations of General Relativity (GR) describing a homogeneous and isotropic universe together with its linear and higher-order perturbations are the theoretical roots of the current standard model of…

General Relativity and Quantum Cosmology · Physics 2024-12-20 Marie-Noëlle Célérier

We modify the scalar Einstein-aether theory by breaking the Lorentz invariance of a gravitational theory coupled to a Galileon type scalar field. This is done by introducing a Lagrange multiplier term into the action, thus ensuring that the…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Zahra Haghani , Tiberiu Harko , Hamid Reza Sepangi , Shahab Shahidi

The Cosmological Principle (CP) -- the notion that the Universe is spatially isotropic and homogeneous on large scales -- underlies a century of progress in cosmology. It is conventionally formulated through the…

A field theory is proposed where the regular fermionic matter and the dark fermionic matter are different states of the same "primordial" fermion fields. In regime of the fermion densities typical for normal particle physics, the primordial…

General Relativity and Quantum Cosmology · Physics 2007-05-23 E. I. Guendelman , A. B. Kaganovich

We construct a FLRW universe considering an anisotropic scaling between space and time at extremely high and low energies only. In this context, Friedmann equations contain an additional term arising from spatial curvature which implements…

General Relativity and Quantum Cosmology · Physics 2018-12-26 Rodrigo Maier , Ivano Damião Soares

Among the suggested solutions to the cosmological constant problem, we find the idea of a dynamic vacuum, with an energy density decaying with the universe expansion. We investigate the possibility of a variation in the gravitational…

General Relativity and Quantum Cosmology · Physics 2011-08-17 Saulo Carneiro

This article reviews an approach for constructing a simple relativistic fractal cosmology whose main aim is to model the observed inhomogeneities of the distribution of galaxies by means of the Lemaitre-Tolman solution of Einstein's field…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-27 Marcelo B. Ribeiro

A model for the Universe is proposed whose constituents are: (a) a dark energy field modeled by a fermionic field non-minimally coupled with the gravitational field, (b) a matter field which consists of pressureless baryonic and dark matter…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. O. Ribas , F. P. Devecchi , G. M. Kremer

The aim of this paper is to check if the models with realistic inhomogeneous matter distribution and without cosmological constant can explain the dimming of the supernovae in such a way that it can be interpreted as an acceleration of the…

Astrophysics · Physics 2014-10-13 Krzysztof Bolejko

How does inhomogeneity affect our interpretation of cosmological observations? It has long been wondered to what extent the observable properties of an inhomogeneous universe differ from those of a corresponding…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-28 John T. Giblin , James B. Mertens , Glenn D. Starkman

On small scales the observable Universe is highly inhomogeneous, with galaxies and clusters forming a complex web of voids and filaments. The optical properties of such configurations can be quite different from the perfectly smooth…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Viraj A. A. Sanghai , Pierre Fleury , Timothy Clifton

Without exceeding the limits of the conventional $\Lambda$CDM paradigm, we argue for Yukawa law of interparticle interaction as the law of gravitation in the real expanding inhomogeneous Universe. It covers the whole space and comes up to…

General Relativity and Quantum Cosmology · Physics 2017-09-08 Maxim Eingorn

In this work, we have discussed the Maxwell's electrodynamics in non-linear forms in FRW universe. The energy density and pressure for non-linear electrodynamics have been written in the electro-magnetic universe. The Einstein's field…

General Physics · Physics 2012-08-29 Tanwi Bandyopadhyay , Ujjal Debnath

Isotropic inhomogeneous dust universes are analysed via observational coordinates based on the past light cones of the observer's galactic worldline. The field equations are reduced to a single first--order {\sc ode} in observational…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Roy Maartens , Neil Humphreys , David Matravers , Bill Stoeger

In the framework of polynomial Palatini cosmology, we investigate a simple cosmological homogeneous and isotropic model with matter in the Einstein frame. We show that in this model during cosmic evolution, it appears the early inflation…

General Relativity and Quantum Cosmology · Physics 2018-05-22 Marek Szydlowski , Aleksander Stachowski

We perform three-dimensional numerical relativity simulations of homogeneous and inhomogeneous expanding spacetimes, with a view towards quantifying non-linear effects from cosmological inhomogeneities. We demonstrate fourth-order…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Hayley J. Macpherson , Paul D. Lasky , Daniel J. Price

Using the model based on the Regge-like laws, new analytical formulas are obtained for the moment of inertia, the rotation frequency, and the radius of astronomical non-exotic objects (planets, stars, galaxies, and clusters of galaxies).…

Classical Physics · Physics 2021-05-12 G. G. Adamian , N. V. Antonenko , H. Lenske , V. V. Sargsyan

A field theory is proposed where the regular fermionic matter and the dark fermionic matter are different states of the same "primordial" fermion fields. In regime of the fermion densities typical for normal particle physics, the primordial…

High Energy Physics - Theory · Physics 2016-11-09 E. I. Guendelman , A. B. Kaganovich

In an earlier paper I proposed a highly symmetric semi-classical initial condition to describe the universe in the period leading up to the electroweak transition and completely determine all cosmology after that. Nothing beyond the…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-25 Daniel Friedan

We investigate structure formation in a one dimensional model of a matter-dominated universe using a quasi-newtonian formulation. In addition to dark matter, luminous matter is introduced to examine the potential bias in the distributions.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Yui Shiozawa , Bruce N. Miller