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相关论文: Constraining a bulk viscous matter-dominated cosmo…

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This study investigates the dynamics of a spatially homogeneous and anisotropic LRS Bianchi type-I universe with viscous fluid in the framework of $f(Q)$ symmetric teleparallel gravity. We assume a linear form for $f(Q)$ and introduce…

广义相对论与量子宇宙学 · 物理学 2024-04-16 M. Koussour , S. H. Shekh , M. Bennai , N. Myrzakulov

A simple model of uniformly expanding, homogeneous Universe with a bulk viscosity is studied wherein the inflationary density decays due to viscous dissipation during the expansion phase of the Universe. The model is shown to generate the…

广义相对论与量子宇宙学 · 物理学 2020-10-14 Sanved Kolekar , S. Shankaranarayanan , S. M. Chitre

A generalized dynamical equation for the scale factor of the universe is proposed to describe the cosmological evolution, of which the $\Lambda$CDM model is a special case. It also provides a general example to show the equivalence of the…

天体物理学 · 物理学 2009-11-11 J. Ren , X. H. Meng

The cosmic curvature $\Omega_{K}$ is an important parameter related to the inflationary cosmology and the ultimate fate of the universe. In this work, we adopt the non-CMB observations to constrain $\Omega_{K}$ in the $\Lambda$CDM model and…

宇宙学与河外天体物理 · 物理学 2025-09-12 Peng-Ju Wu , Xin Zhang

We investigate the validity of the Cosmological Principle by constraining the cosmological parameters $H_0$ and $q_0$ through the celestial sphere. Our analyses are performed in a low-redshift regime in order to follow a model independent…

宇宙学与河外天体物理 · 物理学 2016-02-04 C. A. P. Bengaly, , A. Bernui , J. S. Alcaniz

In this paper, we present a scheme to investigate the opacity of the Universe in a cosmological-model-independent way, with the combination of current and future measurements of type Ia supernova sample and galactic-scale strong…

宇宙学与河外天体物理 · 物理学 2020-01-08 Yu-Bo Ma , Shuo Cao , Jia Zhang , Jingzhao Qi , Tonghua Liu , Yuting Liu , Shuaibo Geng

The standard model of cosmology, {\Lambda}CDM, is the simplest model that matches the current observations, but it relies on two hypothetical components, to wit, dark matter and dark energy. Future galaxy surveys and cosmic microwave…

宇宙学与河外天体物理 · 物理学 2018-08-13 Cyrille Doux , Mariana Penna-Lima , Sandro D. P. Vitenti , Julien Tréguer , Eric Aubourg , Ken Ganga

We examine the constraints that can be obtained on standard cold dark matter models from the most currently used data set: CMB anisotropies, type Ia supernovae and the SDSS luminous red galaxies. We also examine how these constraints are…

天体物理学 · 物理学 2015-05-13 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski

We use the Radial Baryon Acoustic Oscillation (RBAO) measurements, distant type Ia supernovae (SNe Ia), the observational $H(z)$ data (OHD) and the Cosmic Microwave Background (CMB) shift parameter data to constrain cosmological parameters…

宇宙学与河外天体物理 · 物理学 2015-05-18 Zhong-Xu Zhai , Hao-Yi Wan , Tong-Jie Zhang

We consider some background tests of standard cosmology in the context of Horava gravity with different scaling dimensions for space and time, which has been proposed as a renormalizable, higher-derivative, Lorentz-violating quantum gravity…

高能物理 - 理论 · 物理学 2022-10-19 Nils A. Nilsson , Mu-In Park

Exact solutions for a model with variable $G$, $\Lambda$ and bulk viscosity are obtained. Inflationary solutions with constant (de Sitter-type) and variable energy density are found. An expanding anisotropic universe is found to isotropize…

广义相对论与量子宇宙学 · 物理学 2014-11-17 Arbab I. Arbab

Inspired by the recent conjecture originated from graduated dark energy that the Universe has recently transitioned from anti-de Sitter vacua to de Sitter vacua, we extend the $\Lambda$CDM model by a cosmological constant ($\Lambda_{\rm…

宇宙学与河外天体物理 · 物理学 2021-12-07 Ozgur Akarsu , Suresh Kumar , Emre Ozulker , J. Alberto Vazquez

It has been recently shown that the presence of a vector field over cosmological scales could explain the observed accelerated expansion of the universe without introducing neither new scales nor unnatural initial conditions in the early…

宇宙学与河外天体物理 · 物理学 2015-05-13 Jose Beltran Jimenez , Ruth Lazkoz , Antonio L. Maroto

In the generalized matter-geometry coupling theory, we investigate the physical characteristics and causality of some new cosmological models for a flat, homogeneous, and isotropic spacetime filled with stiff, radiation, dust, and curvature…

广义相对论与量子宇宙学 · 物理学 2025-04-10 Dinesh Chandra Maurya , Javlon Rayimbaev , Inomjon Ibragimov , Sokhibjan Muminov

We use the physically-consistent tilted spatially-flat and untilted non-flat $\Lambda$CDM inflation models to constrain cosmological parameter values with the Planck 2015 cosmic microwave background (CMB) anisotropy data and recent Type Ia…

宇宙学与河外天体物理 · 物理学 2019-09-19 Chan-Gyung Park , Bharat Ratra

In this work we investigate the utility of using SNe Ia observations in constraining the cosmological parameters in BSBM theory where a scalar field is responsible for both fine structure constant variation and late time universe…

广义相对论与量子宇宙学 · 物理学 2015-06-04 H. Farajollahi , A. Salehi

We present constraints on extensions to the $\Lambda$CDM cosmological model from measurements of the $E$-mode polarization auto-power spectrum and the temperature-$E$-mode cross-power spectrum of the cosmic microwave background (CMB) made…

宇宙学与河外天体物理 · 物理学 2021-10-13 L. Balkenhol , D. Dutcher , P. A. R. Ade , Z. Ahmed , E. Anderes , A. J. Anderson , M. Archipley , J. S. Avva , K. Aylor , P. S. Barry , R. Basu Thakur , K. Benabed , A. N. Bender , B. A. Benson , F. Bianchini , L. E. Bleem , F. R. Bouchet , L. Bryant , K. Byrum , J. E. Carlstrom , F. W. Carter , T. W. Cecil , C. L. Chang , P. Chaubal , G. Chen , H. -M. Cho , T. -L. Chou , J. -F. Cliche , T. M. Crawford , A. Cukierman , C. Daley , T. de Haan , E. V. Denison , K. Dibert , J. Ding , M. A. Dobbs , W. Everett , C. Feng , K. R. Ferguson , A. Foster , J. Fu , S. Galli , A. E. Gambrel , R. W. Gardner , N. Goeckner-Wald , R. Gualtieri , S. Guns , N. Gupta , R. Guyser , N. W. Halverson , A. H. Harke-Hosemann , N. L. Harrington , J. W. Henning , G. C. Hilton , E. Hivon , G. P. Holder , W. L. Holzapfel , J. C. Hood , D. Howe , N. Huang , K. D. Irwin , O. B. Jeong , M. Jonas , A. Jones , T. S. Khaire , L. Knox , A. M. Kofman , M. Korman , D. L. Kubik , S. Kuhlmann , C. -L. Kuo , A. T. Lee , E. M. Leitch , A. E. Lowitz , C. Lu , S. S. Meyer , D. Michalik , M. Millea , J. Montgomery , A. Nadolski , T. Natoli , H. Nguyen , G. I. Noble , V. Novosad , Y. Omori , S. Padin , Z. Pan , P. Paschos , J. Pearson , C. M. Posada , K. Prabhu , W. Quan , A. Rahlin , C. L. Reichardt , D. Riebel , B. Riedel , M. Rouble , J. E. Ruhl , J. T. Sayre , E. Schiappucci , E. Shirokoff , G. Smecher , J. A. Sobrin , A. A. Stark , J. Stephen , K. T. Story , A. Suzuki , K. L. Thompson , B. Thorne , C. Tucker , C. Umilta , L. R. Vale , K. Vanderlinde , J. D. Vieira , G. Wang , N. Whitehorn , W. L. K. Wu , V. Yefremenko , K. W. Yoon , M. R. Young

We use HII starburst galaxy apparent magnitude measurements to constrain cosmological parameters in six cosmological models. A joint analysis of HII galaxy, quasar angular size, baryon acoustic oscillations peak length scale, and Hubble…

宇宙学与河外天体物理 · 物理学 2020-08-14 Shulei Cao , Joseph Ryan , Bharat Ratra

In this work, we have proposed a general dark energy density parametrization to study the evolution of the universe. We have also constrained the model parameters using the combination of Type Ia supernova (SNIa), baryonic acoustic…

广义相对论与量子宇宙学 · 物理学 2018-07-25 Abdulla Al Mamon