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Related papers: FRW Cosmology in $f(Q,T)$ Gravity

200 papers

We investigate the evolution of a spatially flat Friedmann-Robertson-Walker (FRW) universe in the framework of scalar non-metricity theory of gravity. In the model, we consider dark matter (DM) and dark energy (DE) described by the scalar…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Bikash Chandra Roy , Bikash Chandra Paul

In this paper, we introduce bulk viscosity in the formalism of modified gravity theory in which the gravitational action contains a general function $f(R,T)$, where $R$ and $T$ denote the curvature scalar and the trace of the…

General Relativity and Quantum Cosmology · Physics 2015-03-02 C. P. Singh , Pankaj Kumar

Trace-free Einstein gravity, in the absence of matter fields and using the Friedmann-Robertson-Walker (FRW) metric, is solvable both classically and quantum mechanically. This is achieved by using the conformal time as the time variable and…

General Relativity and Quantum Cosmology · Physics 2025-06-06 Merced Montesinos , Abdel Pérez-Lorenzana , Jorge Meza , Diego Gonzalez

This research article presents a new cosmological model formulated within the $f(R,G,T)$ framework, focusing on the observational signatures and parameter constraints of the model. The Markov Chain Monte Carlo (MCMC) technique is employed…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Himanshu Chaudhary , Amine Bouali , Niyaz Uddin Molla , Ujjal Debnath , G. Mustafa

Motivated by recent work on consistent fluid couplings in $f(R, T)$ gravity, we study cosmology in the nontrivial model $f(R, T) = R + \sigma R T$ using the Brown variational principle for a barotropic perfect fluid. For a flat FLRW…

General Relativity and Quantum Cosmology · Physics 2026-05-15 Davide Batic , Christian G. Boehmer , Denys Dutykh

The evolution of spatially homogeneous and isotropic cosmological models containing a perfect fluid with equation of state p=w\rho\ and a cosmological constant \Lambda\ is investigated for arbitrary combinations of w and \Lambda, using…

Physics Education · Physics 2012-09-19 Sebastiano Sonego , Vittorino Talamini

The expansion of the universe in $f(R,T)$ gravity is studied. By focusing on functions of the form $f(R,T)=f_1(R)+f_2(T)$, we assert that present day acceleration can be achieved if the functional form of $f_2(T)$ either grows slowly or…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Vincent R. Siggia , Eric D. Carlson

In this work, we investigate a cosmological scenario with a time-dependent cosmological constant $\Lambda$(t) within the spatially flat Friedmann-Lema\^itre-Robertson-Walker (FLRW) framework. Here we study a power-law $\Lambda(t)$CDM model…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Archana Dixit , Manish Yadav , Anirudh Pradhan , M. S. Barak

In this paper, cosmic distance duality relation is probed without considering any background cosmological model. The only \textit{a priori} assumption is that the Universe is described by the Friedmann-Lema$\hat{i}$tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2025-01-28 Savita Gahlaut

In this paper, we consider an open system from the thermodynamic perspective for an adiabatic FRW universe model in which particle creation occurs within the system. In that case, the modified continuity equation is obtained and then we…

General Relativity and Quantum Cosmology · Physics 2022-12-14 S. Ganjizadeh , Alireza Amani , M. A. Ramzanpour

In this paper, we investigate a cosmological model based on viscous $f(R,T)$ gravity as a potential alternative to dark energy. This model incorporates bulk viscosity and is analyzed using an effective equation of state. We consider the…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-26 M. Koussour , A. Altaibayeva , S. Bekov , O. Donmez , S. Muminov , J. Rayimbaev

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

We consider the purely gravitational fourth-order (in the spacetime curvature) quantum corrections to the Einstein-Hilbert gravity action, coming from superstrings in the leading order with respect to the Regge slope parameter, and study…

High Energy Physics - Theory · Physics 2008-11-26 M. Iihoshi , S. V. Ketov

This paper investigates the cosmological implications of the modified gravity framework known as $f(R,\Sigma, T)$ gravity, focusing on its potential to unify and extend current cosmological models. The theory, introduced by Bakry and…

General Relativity and Quantum Cosmology · Physics 2025-03-04 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan

In this paper, we have studied the late-time accelerating expansion of the Universe using the matter-geometry coupled $ f(Q, T) $ gravity model, where $ Q $ is the non-metricity scalar and $ T $ represents the trace of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2025-03-03 Shambel Sahlu , Bhupendra Kumar Shukla , Rishi Kumar Tiwari , Değer Sofuoğlu , Alnadhief H. A. Alfedeel

In this paper, we explore power law solution of FLRW universe model that is associated with a variable cosmological term $\Lambda(t)$ as a linear function of $\frac{\ddot{a}}{a}, (\frac{\dot{a}}{a})^2$ and $\rho$. The model parameters were…

General Physics · Physics 2025-04-28 G. K. Goswami , Anirudh Pradhan

In this exclusive study of the modified $f(Q)$ theory of gravity in the open and closed type Friedmann-Lema\^itre-Robertson-Walker (FLRW) universe model, we impose some constraints from the classical energy conditions. The viable range of…

General Relativity and Quantum Cosmology · Physics 2023-06-07 Ganesh Subramaniam , Avik De , Tee-How Loo , Yong Kheng Goh

In this work, we developed a cosmological model in $ f(Q, C) $ gravity within the framework of symmetric teleparallel geometry. In addition to the non-metricity scalar $Q $, our formulation includes the boundary term $ C $, which accounts…

General Relativity and Quantum Cosmology · Physics 2024-11-12 Shaily , J. K. Singh , Mohit Tyagi , Joao R. L. Santos

The paper deals with the definition of gravitational energy in conformal teleparallel gravity. The total energy is defined by means of the field equations which allow a local conservation law. Then such an expression is analyzed for a…

General Relativity and Quantum Cosmology · Physics 2017-11-28 J. G. da Silva , S. C. Ulhoa

We study an extension of symmetric teleparallel gravity i.e. Weyl-type $f(Q,T)$ gravity and the divergence-free parametrization of the deceleration parameter $q(z) = q_{0}+q_{1}\frac{z(1+z)}{1+z^2}$ ($q_{0}$ and $q_{1}$ are free constants)…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Gaurav N. Gadbail , Simran Arora , Praveen Kumar , P. K. Sahoo