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Related papers: {\Lambda}CDM-Rastall cosmology revisited: constrai…

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We investigate the universe's evolution within the framework of Rastall gravity, which is an extension of the standard $\Lambda$CDM model. Utilizing a linear parametrization of the Equation of State (EoS) in a…

General Relativity and Quantum Cosmology · Physics 2024-10-17 J. K. Singh , Akanksha Singh , Shaily , Sushant G. Ghosh , Sunil D. Maharaj

This study conducts a meticulous examination of the cosmological implications inherent in Rastall gravity and $f(R)$ gravity models, assessing their efficacy across distinct cosmic epochs, from early universe structure formation to…

General Relativity and Quantum Cosmology · Physics 2025-01-14 Muhammad Yarahmadi , Amin Salehi , Hadis Mousavi

We present a detailed investigation of the Rastall gravity extension of the standard $\Lambda$CDM model. We review the model for two simultaneous modifications of different nature in the Friedmann equation due to the Rastall gravity: the…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-17 Ozgur Akarsu , Nihan Katirci , Suresh Kumar , Rafael C. Nunes , Burcu Ozturk , Shivani Sharma

Rastall gravity theory shows notable features consistent with physical observations in comparison to the standard Einstein theory. Recently, there has been a debate about the equivalence of Rastall gravity and general relativity. Motivated…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Wompherdeiki Khyllep , Jibitesh Dutta

The Rastall's theory is a modification of General Relativity touching one of the cornestone of gravity theory: the conservation laws. In Rastall's theory, the energy-momentum tensor is not conserved anymore, depending now on the gradient of…

General Relativity and Quantum Cosmology · Physics 2015-06-19 J. C. Fabris , O. F. Piattella , D. C. Rodrigues , M. H. Daouda

In this investigation, we perform an observational statistical analysis in the theory of $ f(R, L_m) $ gravity. The proposed theoretical model is based on the Ricci scalar's non-linear contribution. We use a distinct parameterization for…

General Relativity and Quantum Cosmology · Physics 2024-08-30 J. K. Singh , Shaily , Akanksha Singh , Harshna Balhara , Joao R. L. Santos

In this manuscript, we investigate the constraints on dynamical vacuum models within the framework of $\Lambda(t)$CDM cosmology by assuming a parameterization of the vacuum energy density as $\rho_{\Lambda}(t)=\rho_{\Lambda 0} \left[1 +…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-14 Yerlan Myrzakulov , M. Koussour , M. Bulanbay , S. Muminov , J. Rayimbaev

In this work we study the phase-space analysis of generalized Rastall gravity (GRG) which has recently been introduced as a modification to the original version of Rastall gravity (RG). In GRG, the coupling parameter assumes a dynamical…

General Relativity and Quantum Cosmology · Physics 2022-06-01 Hamid Shabani , Hooman Moradpour , Amir Hadi Ziaie

We study the late-time evolution of the Universe within the f(R,G) gravity framework, where R is the Ricci scalar and G is the Gauss-Bonnet term. To make the model tractable, we propose a parametrization scheme and determine its parameters…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Santosh V. Lohakare , B. Mishra , S. K. Maurya

We carry out a comparative analysis of the standard $\Lambda$CDM cosmological model and the alternative $R_h=ct$ framework using recent observational data from cosmic chronometers (CC), Type Ia supernova, and baryon acoustic oscillations.…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-26 Amritansh Mehrotra , S. K. J. Pacif , A. F. Santos

Rastall's theory is a modification of General Relativity, based on the non-conservation of the stress-energy tensor. The latter is encoded in a parameter $\gamma$ such that $\gamma = 1$ restores the usual $\nabla_\nu T^{\mu\nu} = 0$ law. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 C. E. M. Batista , J. C. Fabris , O. F. Piattella , A. M. Velasquez-Toribio

In the paper, we present an accelerating cosmological model in $f(R,\mathcal{L}_{m})$ gravity with the parameter constrained through the cosmological data sets. At the beginning, we have employed a functional form of $f(R,\mathcal{L}_{m})…

General Relativity and Quantum Cosmology · Physics 2025-01-10 Y. Kalpana Devi , S. A. Narawade , B. Mishra

We study cosmological constraints on the various accelerating models of the universe using the time evolution of the cosmological redshift of distant sources. The important characteristic of this test is that it directly probes the…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Deepak Jain , Sanjay Jhingan

Recently a modified version of Rastall theory of gravity has been introduced in which a varying coupling parameter could act as dark energy (DE) and thus, it can be held responsible for the current accelerated expansion of the Universe.…

General Physics · Physics 2020-11-20 A. H. Ziaie , H. Moradpour , H. Shabani

As an important candidate gravity theory alternative to dark energy, a class of $f(R)$ modified gravity, which introduces a perturbation of the Ricci scalar $R$ in the Einstein-Hilbert action, has been extensively applied to cosmology to…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-18 Tengpeng Xu , Shuo Cao , Jingzhao Qi , Marek Biesiada , Xiaogang Zheng , Zong-Hong Zhu

The absence of guidance from fundamental physics about the mechanism behind cosmic acceleration has given rise to a number of alternative cosmological scenarios. These are based either on modifications of general relativistic gravitation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 M. A. Dantas , J. S. Alcaniz , D. Mania , Bharat Ratra

The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-17 Muhammad Omer Farooq

In this paper we place observational constraints on the well-known $\gamma$-gravity $f(R)$ model using the latest cosmological data, namely we use the latest growth rate, Cosmic Microwave Background, Baryon Acoustic Oscillations, Supernovae…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-17 Clara Álvarez Luna , Spyros Basilakos , Savvas Nesseris

In this work, a new generic parameterisation for $f(R)$ theories is presented. Our proposal for a new equation of state can reproduce an $f(R)$-like evolution that describes late and early time universe within 1-$\sigma$ C.L when we use a…

General Relativity and Quantum Cosmology · Physics 2020-11-20 N. M. Jiménez Cruz , Celia Escamilla-Rivera

The concordance (LambdaCDM) model reproduces the main current cosmological observations assuming the validity of general relativity at all scales and epochs, the presence of cold dark matter, and of a cosmological constant, equivalent to a…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-08 Guido Risaliti , Elisabeta Lusso
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