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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, a cosmological model of the Universe is presented in $f(Q,T)$ gravity and the parameters are constrained by cosmological data sets. Initially, a generalised form of $f(Q,T)$ model is used as $f(Q,T)=-\lambda_{1}…

General Relativity and Quantum Cosmology · Physics 2024-03-21 A. S. Agrawal , B. Mishra , S. K. Tripathy

The fundamental nature and origin of dark energy are one of the premier mysteries of theoretical physics. In General Relativity Theory, the cosmological constant $\Lambda$ is the simplest explanation for dark energy. On the other hand, the…

General Relativity and Quantum Cosmology · Physics 2022-05-27 Raja Solanki , Avik De , Sanjay Mandal , P. K. Sahoo

This study explores a distinctive logarithmic parameterization of the deceleration parameter within the $f(Q, C)$ gravity framework, incorporating a nonlinear functional form $f(Q, C) = \gamma_1 Q^n + \gamma_2 C$, where $Q$ and $C$ denote…

General Relativity and Quantum Cosmology · Physics 2025-06-03 S. R. Bhoyar , Yash B. Ingole

We investigate a dark energy (DE) equation of state (EoS) parametrization in a curved spacetime using current observations. We constrain the model parameters by using observational Hubble data from Cosmic Chronometer (CC), Pantheon Plus…

General Physics · Physics 2026-05-13 D. Revanth Kumar , Santosh Kumar Yadav

We study a parametrization of the deceleration parameter in a tilted universe, namely a cosmological model equipped with two families of observers. The first family follows the smooth Hubble flow, while the second are the real observers…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Kerkyra Asvesta , Lavrentios Kazantzidis , Leandros Perivolaropoulos , Christos G. Tsagas

In the following work, a new hybrid model of the form $ f(Q)=Q(1+a)+b\frac{Q_0^2}{Q} $ has been proposed and confronted using both early as well as late-time constraints. We first use conditions from the era of Big Bang Nucleosynthesis…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Ameya Kolhatkar , Sai Swagat Mishra , P. K. Sahoo

We study the robustness and physical implications of a set of characteristic redshifts that capture key features of the late-time Universe. Using both model-independent reconstructions as well as different dark energy (DE)…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-13 Shibendu Gupta Choudhury , Purba Mukherjee , Anjan Ananda Sen

A parametric reconstruction of the jerk parameter, the third order derivative of the scale factor expressed in a dimensionless way, has been discussed. Observational constraints on the model parameters have been obtained by Maximum…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Ankan Mukherjee , Narayan Banerjee

We study cosmological evolution in a flat FLRW spacetime in the context of modified STEGR gravity or $f(Q)$, using an exponential two-parameter model which represents a smooth perturbative expansion around the $\Lambda$CDM model. The…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Ivan R. Vasquez , A. Oliveros

One of the most compelling tasks of modern cosmology is to constrain the expansion history of the Universe, since this measurement can give insights on the nature of dark energy and help to estimate cosmological parameters. In this letter…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Michele Moresco

In this article, we investigate the modified symmetric teleparallel gravity or $f(Q)$ gravity, where $Q$ is the non-metricity, to study the evolutionary history of the universe by considering the functional form of $f(Q)=\alpha Q^n$, where…

General Relativity and Quantum Cosmology · Physics 2022-12-16 Gaurav N. Gadbail , Sanjay Mandal , P. K. Sahoo

The $\Lambda$CDM model successfully explains a wide range of cosmological observations; however, persistent discrepancies most notably the $H_0$ tension between early and late time measurements challenge its completeness. No proposed…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Upala Mukhopadhyay , Purba Mukherjee , Alexandre Tkatchenko

The kinematic approach to cosmological tests provides a direct evidence to the present accelerating stage of the universe which does not depend on the validity of general relativity, as well as on the matter-energy content of the Universe.…

Astrophysics · Physics 2009-03-12 J. V. Cunha

This paper aims to put constraints on the transition redshift $z_t$, which determines the onset of cosmic acceleration, in cosmological-model independent frameworks. In order to perform our analyses, we consider a flat universe and {assume}…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-31 J. F. Jesus , R. F. L. Holanda , S. H. Pereira

We probe the cosmic expansion scenario within the framework of $f(R, L_{m})$ gravity by employing a well-motivated functional form of $f(R, L_{m}) = \frac{R}{2} + L_{m}^{\lambda}$. Specifically, we introduce three novel cosmological models…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Khomesh R. Patle , G. P. Singh

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 paper, we examine observational constraints on the power law cosmology; essentially dependent on two parameters $H_0$ (Hubble constant) and $q$ (deceleration parameter). We investigate the constraints on these parameters using the…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Sarita Rani , A. Altaibayeva , M. Shahalam , J. K. Singh , R. Myrzakulov

In this study, we explored late-time cosmology within an extended class of theories based on $f(Q, L_m)$ gravity. This theory generalizes $f(Q)$ gravity by incorporating a non-minimal coupling between the non-metricity $Q$ and the matter…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-07 Kairat Myrzakulov , M. Koussour , O. Donmez , A. Cilli , E. Güdekli , J. Rayimbaev

This study proposes a novel parametrization approach for the dimensionless Hubble parameter i.e. $E^2(z)=A(z)+\beta (1+\gamma B(z))$ in the context of scalar field dark energy models. The parameterization is characterized by two functions,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-09 M. Koussour , N. Myrzakulov , S. Myrzakulova , D. Sofuoğlu
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