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Related papers: Inhomogeneous Cosmology Redux

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In this paper, it is shown that the cosmological model that was introduced in a sequence of three earlier papers under the title, A Dust Universe Solution to the Dark Energy Problem, can be used to resolve the problem of the great mismatch…

General Physics · Physics 2010-07-21 James G. Gilson

We show that a combined analysis of CMB anisotropy power spectra obtained by the Planck satellite and luminosity distance data simultaneously excludes a flat universe and a cosmological constant at $99 \%$ CL. These results hold separately…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-17 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

We perform a cosmographic analysis using several cosmological observables such as the luminosity distance moduli, the volume distance, the angular diameter distance and the Hubble parameter. These quantities are determined using different…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jun-Qing Xia , Vincenzo Vitagliano , Stefano Liberati , Matteo Viel

A local void in the globally Friedmann-Robertson-Walker (FRW) cosmological model is studied. The inhomogeneity is described using the Lema\^{\i}tre-Tolman-Bondi (LTB) solution with the spherically symmetric matter distribution based on the…

Astrophysics · Physics 2009-10-22 J. W. Moffat , D. C. Tatarski

It is shown that cosmological equations for homogeneous isotropic models deduced in the framework of the Poincar\'e gauge theory of gravity by certain restrictions on indefinite parameters of gravitational Lagrangian take at asymptotics the…

General Relativity and Quantum Cosmology · Physics 2009-09-29 A. V. Minkevich

Problems with the concordance cosmology $\Lambda$CDM as the cosmological constant problem, coincidence problems and Hubble tension has led to many proposed alternatives, as the $\Lambda(t)$CDM, where the now called $\Lambda$ cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-03 H. A. P. Macedo , L. S. Brito , J. F. Jesus , M. E. S. Alves

A potential solution to the Hubble tension is the hypothesis that the Milky Way is located near the center of a matter underdensity. We model this scenario through the Lema\^itre-Tolman-Bondi formalism with the inclusion of a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-07 Sveva Castello , Marcus Högås , Edvard Mörtsell

Assuming homogeneous isotropic Lambda-CDM cosmology allows Lambda, spatial curvature and dark matter density to be inferred from large scale structure observations such as supernovae. The purpose of this paper is to extend this to allow…

General Relativity and Quantum Cosmology · Physics 2011-02-02 Toby Wiseman , Benjamin Withers

In this paper, we study Friedmann cosmology with time-varying vacuum energy density in the context of Brans-Dicke theory. We consider an isotropic and homogeneous flat space, filled with a matter-dominated perfect fluid and a dynamical…

General Relativity and Quantum Cosmology · Physics 2024-01-09 C. P. Singh , Joan Sola Peracaula

We present new cosmological constraints in a set of motivated extensions of the $\Lambda$CDM model using the polarization and gravitational lensing measurements from the South Pole Telescope and the Planck CMB temperature observations at…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-14 Anton Chudaykin , Dmitry Gorbunov , Nikita Nedelko

It is commonly stated that we have entered the era of precision cosmology in which a number of important observations have reached a degree of precision, and a level of agreement with theory, that is comparable with many Earth-based physics…

General Physics · Physics 2011-10-31 Marie-Noëlle Célérier

Recently there have been claims on model-independent evidence of dynamical dark energy. Herein we consider a fairly general class of cosmological models with a time-evolving cosmological term of the form $\Lambda(H)=C_0+C_H H^2+C_{\dot{H}}…

General Relativity and Quantum Cosmology · Physics 2015-10-08 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez

We consider spherically symmetric inhomogeneous dust models with a positive cosmological constant, $\Lambda$, given by the Lemaitre-Tolman-Bondi metric. These configurations provide a simple but useful generalization of the Lambda-CDM model…

General Relativity and Quantum Cosmology · Physics 2015-03-14 Roberto A. Sussman , German Izquierdo

We discuss inhomogeneous cosmological models which satisfy the Copernican principle. We construct some inhomogeneous cosmological models starting from the ansatz that the all the observers in the models view an isotropic cosmic microwave…

General Relativity and Quantum Cosmology · Physics 2015-06-25 C. A. Clarkson , A. A. Coley , E. S. D. O'Neill , R. A. Sussman , R. K. Barrett

The fundamental laws of physics are required to be invariant under local spatial scale change. In 3-dimensional space, this leads to a variation in Planck constant \hbar and speed of light c. They vary as \hbar ~ a^(1/2) and c ~ a^(-1/2), a…

General Physics · Physics 2013-02-28 Hoang K. Nguyen

Supernovae observations strongly support the presence of a cosmological constant, but its value, which we will call apparent, is normally determined assuming that the Universe can be accurately described by a homogeneous model. Even in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Antonio Enea Romano , Pisin Chen

In a previous work it was shown that by considering the quantum nature of the gravitational field mediator, it is possible to introduce the momentum energy of the graviton into the Einstein equations as an effective cosmological constant.…

General Physics · Physics 2022-03-16 Tonatiuh Matos , Luis Osvaldo Tellez-Tovar

Voids are dominant features of the cosmic web. We revisit the cosmological information content of voids and connect void properties with the parameters of the background universe. We combine analytical results with a suite of large n-body…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-24 Benjamin C. Bromley , Margaret J. Geller

We present a comprehensive analysis of the $\Lambda_{\rm s}$CDM model, which explores the recent conjecture suggesting a rapid transition of the Universe from anti-de Sitter vacua to de Sitter vacua (viz., the cosmological constant switches…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-21 Ozgur Akarsu , Eleonora Di Valentino , Suresh Kumar , Rafael C. Nunes , J. Alberto Vazquez , Anita Yadav

A local void in the globally Friedmann-Robertson-Walker cosmological model with the critical density ($\Omega_{0}=1$) is studied. The inhomogeneity is described using a Lema\^{\i}tre-Tolman-Bondi solution for a spherically symmetric…

Astrophysics · Physics 2008-02-03 J. W. Moffat , D. C. Tatarski
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