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In this manuscript, we studied the accelerated expansion history of the universe and the formations of large-scale structures using $f(Q)$ gravity model. The expansion rate of the universe within distance modulus and redshift has been…

General Relativity and Quantum Cosmology · Physics 2022-06-07 Shambel Sahlu , Endalkachew Tsegaye

In this paper, the dynamical behavior of the accelerated expansion of the universe is studied within the framework of $f(T)$ gravity by considering a well-motivated functional form of $f(T)$. A specific form of the Hubble parameter is…

General Relativity and Quantum Cosmology · Physics 2026-03-20 Khomesh R. Patle , G. P. Singh

Two accelerating cosmological models are presented in symmetric teleparallel $f(Q)$ gravity, $Q$ be the non-metricity. The models are constructed based on the assumptions of two different functional forms of $f(Q)$ and a dynamically…

General Relativity and Quantum Cosmology · Physics 2022-05-25 S. A. Narawade , Laxmipriya Pati , B. Mishra , S. K. Tripathy

We present a new $f(Q)$ cosmological model capable of reproducing late-time acceleration, i.e. $f\left( Q\right) = \lambda_{0}\left( \lambda +Q\right) ^{n}$ by supporting certain parametrization of the Hubble parameter. By using…

General Relativity and Quantum Cosmology · Physics 2023-06-26 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

In this paper we have investigated a bulk viscous universe in $f(R,T)$ gravity where $R$ and $T$ are the Ricci scalar and trace of energy momentum tensor respectively. We have obtained explicit solutions of field equations in modified…

General Physics · Physics 2020-03-03 Anil Kumar Yadav , Lokesh Kumar Sharma , B. K. Singh , P. K. Sahoo

We discuss transport properties of dynamical fluid composed of quasi-particles whose masses depend on temperature and charge chemical potentials. Based on the relativistic kinetic theory formulated under the relaxation time approximation,…

High Energy Physics - Phenomenology · Physics 2009-06-30 C. Sasaki , K. Redlich

In this paper we have discussed the modified gravity and scalar field DE model specifically DBI essence model with the analysis of thermodynamics during cosmological evolution. We have used the modified gravity with the form…

General Physics · Physics 2022-06-02 Shouvik Sadhukhan , Alokananda Kar , Surajit Chattopadhyay

We consider inhomogeneous viscous fluids in flat Friedmann-Robertson-Walker universe. We analyze different kinds of such fluids and investigate the possibility to reproduce the current cosmic acceleration providing a different future…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Shynaray Myrzakul , Ratbay Myrzakulov , Lorenzo Sebastiani

The recently proposed $f(Q, T)$ gravity (Xu et al. Eur. Phys. J. C \textbf{79} (2019) 708) is an extension of the symmetric teleparallel gravity. The gravitational action $L$ is given by an arbitrary function $f$ of the non-metricity $Q$…

General Relativity and Quantum Cosmology · Physics 2020-10-02 Simran Arora , P. K. Sahoo

We discuss the connection among three distinct classes of models often used to explain the late cosmic acceleration: decaying cosmological term, bulk viscous pressure, and nonlinear fluids. We focus on models that are equivalent at zeroth…

Astrophysics · Physics 2007-05-23 Sandro Silva e Costa , Martin Makler

We present a discussion of the effects induced by bulk viscosity on the very early Universe stability. The viscosity coefficient is assumed to be related to the energy density $\rho$ via a power-law of the form $\zeta=\zeta_0 \rho^s$ (where…

General Relativity and Quantum Cosmology · Physics 2009-03-24 Nakia Carlevaro , Giovanni Montani

Two parameters scale factor leading to bouncing cosmology is considered. We show that at some model parameters we obtain the deceleration parameter $q_0\approx -0.535$ at the current epoch which is in agreement with the Planck data. The…

General Physics · Physics 2026-05-18 S. I. Kruglov

The concept of negative temperatures has occasionally been used in connection with quantum systems. A recent example of this sort is reported in the paper of S. Braun et al. [Science 339,52 (2013)], where an attractively interacting…

General Relativity and Quantum Cosmology · Physics 2013-10-01 Iver Brevik , Øyvind Grøn

In this study, we analyze the anisotropic universe in $f(Q,C)$ gravity theory. To achieve this, we consider three specific models of $f(Q,C)$ gravity and rewrite the equations of motion of each model as an autonomous system. We identify and…

General Relativity and Quantum Cosmology · Physics 2025-05-14 Ghulam Murtaza , Avik De , Tee-How Loo , Yong Kheng Goh , How Hui Liew

In the past few years, $f(Q)$ theories have drawn a lot of research attention in replacing Einstein's theory of gravity successfully. The current study examines the novel cosmological possibilities emerging from two specific classes of…

General Relativity and Quantum Cosmology · Physics 2023-05-31 M. Koussour , Avik De

Conformally flat tilted Bianchi type V cosmological models in presence of a bulk viscous fluid and heat flow are investigated. The coefficient of bulk viscosity is assumed to be a power function of mass density. Some physical and geometric…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Anirudh Pradhan , Abha Rai

We investigate classes of shear-free cosmological dust models with irrotational fluid flows within the framework of $f(T)$ gravity. In particular, we use the $1 + 3$ covariant formalism and present the covariant linearised evolution and…

General Relativity and Quantum Cosmology · Physics 2022-07-27 Heba Sami , Shambel Sahlu , Amare Abebe , Peter K. S. Dunsby

The effect of bulk viscisity on the evolution of the homogeneous and isotropic cosmological models is considered. Solutions are found, with a barotropic equation of state, and a viscosity coefficient that is proportional to a power of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pimentel L O , Diaz-Rivera L M

We present the cosmic expansion scenario in the framework of $f(T)$ gravity by employing a dark energy equation of state (EoS) parameter. Specifically, we proceed with the power-law form of the function $f(T) = \alpha$$(-T)^{n}$, in…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Khomesh R. Patle , G. P. Singh

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