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Related papers: Observational Constraints on Model with specific q

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We propose a Friedmann-Lemaitre-Robertson-Walker cosmological model with a scalar field that represents dark energy. A new parametrization of the deceleration parameter is introduced of the form $q = 1 + \eta (1 + \mu a^{\eta})$ where…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-07 Aroonkumar Beesham

This study delves into the cosmological implications of the $f(Q,C)$ modified gravity framework within the context of the FLRW spacetime which offers a dynamic alternative to the standard $\Lambda$CDM cosmology. Here, we define the transit…

General Relativity and Quantum Cosmology · Physics 2024-12-03 N. Myrzakulov , Anirudh Pradhan , A. Dixit , S. H. Shekh

In this paper within the scope of FRW cosmology for k = 0, \pm1 we study the dynamics of the universe for a cosmological model with a scalar field nonminimally coupled to matter. By best- fitting the model parameters with the observational…

General Relativity and Quantum Cosmology · Physics 2012-07-09 H. Farajollahi , A. Salehi

We place observational constraints on models with the late-time cosmic acceleration based on a number of parametrizations allowing fast transitions for the equation of state of dark energy. In addition to the model of Linder and Huterer…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Antonio De Felice , Savvas Nesseris , Shinji Tsujikawa

We study an isotropic flat FLRW-model in Scale-covariant theory of gravity $ f_{\gamma \delta}(\phi) $ \cite{Canuto:1977zz} which is explained in terms of ordinary and covariant differentiation of scalar field $ \phi $. As we know the…

General Relativity and Quantum Cosmology · Physics 2024-05-01 Shaily , J. K. Singh , Joao R. L. Santos , M. Zeyauddin

In the present paper, we investigate constrained transit cosmological models in the most recent proposed modified gravity theory, $f(R,L_{m},T)$-gravity. We obtain the modified field equations for a flat homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2024-12-20 Dinesh Chandra Maurya

In this paper we present cosmological constraints on several well-known $f(R)$ models, but also on a new class of models that are variants of the Hu-Sawicki one of the form $f(R)=R-\frac{2\Lambda}{1+b\;y(R,\Lambda)}$, that interpolate…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-29 Judit Pérez-Romero , Savvas Nesseris

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

We use the recently released cosmic chronometer data and the latest measured value of the local Hubble parameter, combined with the latest joint light curves of Supernovae Type Ia, and Baryon Acoustic Oscillation distance measurements, in…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-09 Rafael C. Nunes , Supriya Pan , Emmanuel N. Saridakis , Everton M. C. Abreu

We present a phenomenological analysis of current observational constraints on classes of FLRW cosmological models in which the matter side of Einstein's equations includes, in addition to the canonical term, a term proportional to some…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-04 E. -A. Kolonia , C. J. A. P. Martins

In this paper, we have analyzed the geometrical and dynamical parameters of $\mathcal{F}(R, \mathcal{G})=\alpha R^2 \mathcal{G}^\beta$ cosmological model, ($R$, $\mathcal{G}$ being the Ricci scalar and Gauss-Bonnet invariant respectively),…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Santosh V. Lohakare , Krishna Rathore , B. Mishra

We perform a detailed confrontation of various oscillating dark-energy parame-trizations with the latest sets of observational data. In particular, we use data from Joint Light Curve analysis (JLA) sample from Supernoave Type Ia, Baryon…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Supriya Pan , Emmanuel N. Saridakis , Weiqiang Yang

The accelerated expansion of the Universe remains one of the central open problems in modern cosmology. While the $\Lambda$CDM model successfully describes a wide range of observations, the physical nature of dark energy is still unknown,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-08 Leandro Pardo , Leonardo Castañeda

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

In this paper, we study a cosmological model in general relativity within the framework of spatially flat Friedmann-Robertson-Walker space-time filled with ordinary matter (baryonic), radiation, dark matter and dark energy, where the latter…

General Relativity and Quantum Cosmology · Physics 2014-09-04 Suresh Kumar , Lixin Xu

We proposed a model-independent method to constrain the cosmological parameters using the Distance Sum Rule of the FLRW metric by combining the time delay distances and the comoving distances through a multi-messenger approach. The time…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Yufeng Li , Xilong Fan , Lijun Gou

This cosmological model is a study of modified $f(Q,T)$ theory of gravity which was recently proposed by Xu {\it et al.} (Eur. Phys. J. C {\bf 79}, 708 (2019)). In this theory of gravity, the action contains an arbitrary function $f(Q,T)$…

General Physics · Physics 2021-09-03 Anirudh Pradhan , Archana Dixit

Observational tests for the Cosmological Principle are reviewed. Assuming the FRW metric we then summarize estimates of cosmological parameters from various data sets, in particular the Cosmic Microwave Background and the 2dF galaxy…

Astrophysics · Physics 2008-11-26 Ofer Lahav

This paper analyses the cosmological consequences of a modified theory of gravity whose action integral is built from a linear combination of the Ricci scalar $R$ and a quadratic term in the covariant derivative of $R$. The resulting…

General Relativity and Quantum Cosmology · Physics 2015-12-31 R. R. Cuzinatto , C. A. M. de Melo , L. G. Medeiros , P. J. Pompeia

The oscillating scenario of route to Lambda was recently proposed by us arXiv:0704.1651 as an alternative to a cosmological constant in a explanation of the current accelerating universe. In this scenario phantom scalar field conformally…

Astrophysics · Physics 2008-11-26 Aleksandra Kurek , Orest Hrycyna , Marek Szydlowski