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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 $f(R, T)$ theory of gravity extends general relativity (GR) by allowing the gravitational Lagrangian to depend on both the Ricci scalar $R$ and the trace of the energy-momentum tensor $T$. The resulting matter-geometry coupling…

General Relativity and Quantum Cosmology · Physics 2026-02-16 Serkan Doruk Hazinedar , Yaghoub Heydarzade , Shahram Jalalzadeh

We present a novel derivation of scalar cosmological perturbations in the scalar-tensor extension of non-metricity gravity, where the non-metricity scalar $Q$ is non-minimally coupled to a dynamical scalar field. While previous…

General Relativity and Quantum Cosmology · Physics 2025-12-09 Ganesh Subramaniam , Avik De , Jackson Levi Said

In this article, we investigate the cosmological viability of a modified symmetric teleparallel gravity model within the $f(Q)$ framework. We derive observational constraints on the model parameters by performing a Markov Chain Monte Carlo…

General Relativity and Quantum Cosmology · Physics 2026-01-13 S. A. Kadam , D. Revanth Kumar , Santosh Kumar Yadav

Teleparallel gravity is a modified theory of gravity in which the Ricci scalar $R$ of the Lagrangian replaced by the general function of torsion scalar $T$ in action. With that, cosmology in teleparallel gravity becomes profoundly…

General Physics · Physics 2020-09-09 Sanjay Mandal , P. K. Sahoo

As a classical approach, the dynamics of the Universe, influenced by its dark components, are unveiled through prior modifications of Einstein's equations. Cosmography, on the other hand, is a highly efficient tool for reconstructing any…

General Relativity and Quantum Cosmology · Physics 2024-07-19 Sai Swagat Mishra , N. S. Kavya , P. K. Sahoo , V. Venkatesha

Despite the significant accomplishments of general relativity, numerous unresolved issues persist in our understanding of the cosmos. One of the most perplexing challenges is the ongoing accelerated expansion of the Universe, which…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , Amare Abebe

In this article we have presented FRW cosmological model in the framework of Brans-Dicke theory. This paper deals with a new proposed form of deceleration parameter and cosmological constant. The effect of bulk viscosity is also studied in…

General Relativity and Quantum Cosmology · Physics 2017-07-27 G. P. Singh , Binaya K. Bishi

We investigate the divergence-free parametric form of the deceleration parameter within the simplest non-minimal matter-geometry coupling in $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor.…

General Relativity and Quantum Cosmology · Physics 2025-03-11 A. Zhadyranova , M. Koussour , Zh. Kanibekova , V. Zhumabekova , U. Ismail , S. Muminov , J. Rayimbaev

We study the late-time cosmological expansion of a modified teleparallel gravity model of type logarithmic type. This modified gravitational lagrangian yields a cosmological constant term and also power-law corrections to the teleparallel…

General Relativity and Quantum Cosmology · Physics 2025-10-27 Adriel O. Aquino , Euclides G. Silva

To find more deliberate f(R,T) cosmological solutions, we proceed our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

In this article, we attempt to describe cosmic late-time acceleration of the universe in the framework of $f(R,L_m)$ gravity by using an effective equation of state when the account is taken of bulk viscosity. We presume a non-linear…

General Relativity and Quantum Cosmology · Physics 2023-03-31 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , Pradyumn Kumar Sahoo

In this study, the cosmological implications of nonminimally coupled $f(Q)$ gravity are examined within the metric-affine formalism, in which the nonmetricity scalar $Q$ couples directly to the matter Lagrangian. Within the symmetric…

General Relativity and Quantum Cosmology · Physics 2025-11-11 Simran Arora , Mridul Patel

We explore the dynamical properties of a cosmological model that includes viscous effects in the dark matter sector of the fluid equations in a flat Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime. The bulk viscous effects are…

General Relativity and Quantum Cosmology · Physics 2022-11-14 Gilberto Aguilar-Pérez , Ana A. Avilez-López , Miguel Cruz

We study the evolution of a flat Friedmann-Robertson-Walker Universe, filled with a bulk viscous cosmological fluid, in the presence of time varying ``constants''. The dimensional analysis of the model suggests a proportionality between the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 José Antonio Belinchón , Indrajit Chakrabarty

In this article we obtain wormhole solutions in the recently proposed extension of symmetric teleparallel gravity called $f(Q,T)$ gravity. Here, the gravitational Lagrangian $L$ is defined by an arbitrary function $f$ of $Q$ and $T$ (where…

General Relativity and Quantum Cosmology · Physics 2022-08-23 Moreshwar Tayde , Zinnat Hassan , P. K. Sahoo , Sashideep Gutti

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, we first obtain the energy density by the approach of the new agegraphic dark energy model, and then the $f(T,B)$ gravity model is studied as an alternative to the dark energy in a viscous fluid by flat-FRW background, in…

General Relativity and Quantum Cosmology · Physics 2020-06-17 A. Pourbagher , Alireza Amani

We study a minimal modified gravity scenario in the symmetric teleparallel (non-metricity) formulation, focusing on an inverse non-metricity term with $f(Q)=Q+M^4 Q^{-1}$. The model does not introduce additional free parameters relative to…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Luís Atayde , Simão Marques Nunes , Noemi Frusciante

We investigate the exponential $f(Q)$ symmetric teleparallel gravitation, namely $f(Q)=Q+\alpha Q_0(1-e^{-\beta\sqrt{Q/Q_0}})$ using \texttt{ME-GADGET} code to probe the structure formation with box sizes $L_{\mathrm{box}}=10/100$ Mpc$/h$…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-18 Oleksii Sokoliuk , Simran Arora , Subhrat Praharaj , Alexander Baransky , P. K. Sahoo