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Related papers: Constraining model parameters in f(Q,C) gravity: O…

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In this article, the bulk viscosity is introduced in a modified gravity model. The gravitational action has a general $f(R,T)$ form, where $R$ and $ T $ are the curvature scalar and the trace of energy momentum tensor respectively. An…

General Relativity and Quantum Cosmology · Physics 2020-10-02 Simran Arora , Xin-he Meng , S. K. J. Pacif , P. K. Sahoo

This thesis explores the cosmological implications of modified gravity, focusing on nonmetricity-based $f(Q)$ gravity as an alternative to the $\Lambda$CDM model in explaining cosmic acceleration. Chapter I lays the theoretical groundwork…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Gaurav N. Gadbail

This study explores the bouncing solutions within the framework of modified $f(Q, L_m)$ gravity. We examine four prominent bouncing models, the symmetric bounce, super bounce, oscillatory bounce, and matter bounce, each of which has been…

General Relativity and Quantum Cosmology · Physics 2026-04-28 S. A. Kadam , V. A. Kshirsagar , Santosh Kumar Yadav

We have studied bulk viscosity in the modified $f(Q, T)$ gravity theory formalism, where $Q$ represents the non-metricity and $T$ denotes the trace of energy-momentum tensor within a flat Friedmann-Lema\^{i}tre-Robertson-Walker metric…

General Relativity and Quantum Cosmology · Physics 2021-12-01 Simran Arora , S. K. J. Pacif , Abhishek Parida , P. K. Sahoo

In today's scenario, going beyond Einstein's theory of gravity leads us to some more complete and modified gravity theories. One of them is the $f(R,T)$ gravity in which $ R $ is the Ricci scalar, and $ T $ is the trace of the…

General Relativity and Quantum Cosmology · Physics 2022-01-04 P. K. Sahoo , Sanjay Mandal , Simran Arora

In this article, we attempt to explore the dark sector of the universe i.e. dark matter and dark energy, where the dark energy components are related to the modified $f(Q)$ Lagrangian, particularly a power law function $f(Q)= \gamma…

General Relativity and Quantum Cosmology · Physics 2024-05-24 Aaqid Bhat , Raja Solanki , P. K. Sahoo

In this paper, we consider a cosmological model in $ f(R, G) $ gravity in a flat space-time, where $ R $ is the Ricci scalar and $ G $ is the Gauss-Bonnet invariant. The function $ f(R, G) $ is taken as a linear combination of $ R $ and an…

General Relativity and Quantum Cosmology · Physics 2024-07-22 J. K. Singh , Shaily , Anirudh Pradhan , Aroonkumar Beesham

To recreate the cosmological models, we employed the parametrization approach in modified teleparallel Gauss-Bonnet gravity. It has been interesting to apply the parametrization approach to investigate cosmological models. The real benefit…

General Relativity and Quantum Cosmology · Physics 2022-12-29 Santosh V. Lohakare , B. Mishra , S. K. Maurya , Ksh. Newton Singh

This article discusses a dark energy cosmological model in the standard theory of gravity - general relativity with a broad scalar field as a source. Exact solutions of Einstein's field equations are derived by considering a particular form…

General Relativity and Quantum Cosmology · Physics 2022-08-23 S. K. J. Pacif , Simran Arora , P. K. Sahoo

This study effectively reconstructs a cosmological model utilizing covariant $f(Q)$ gravity within Connection-III and FLRW spacetime. The dynamic behavior of the reconstructed model is thoroughly analyzed using the Hubble parameter $H(z)$…

General Relativity and Quantum Cosmology · Physics 2025-01-15 S. A. Narawade , Santosh V. Lohakare , B. Mishra

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

In the context of f(R, T) gravity theory for the flat Friedmann Lemaitre Robertson Walker (FLRW) model, the accelerating expansion of the universe is investigated using a specific form of the emergent Hubble parameter. Datasets from H(z),…

General Relativity and Quantum Cosmology · Physics 2025-01-16 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , Archana Dixit

In this work, we investigate the cosmological dynamics of an anisotropic Universe within the framework of $f(R,T)$ gravity by incorporating pressureless dark matter and the dark energy models. The analysis is carried out in a Bianchi type-I…

General Relativity and Quantum Cosmology · Physics 2026-05-13 S. H. Shekh , N. Myrzakulov , Anirudh Pradhan , M. Zeyauddin

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

We compile an updated list of 38 measurements of the Hubble parameter $H(z)$ between redshifts $0.07 \leq z \leq 2.36$ and use them to place constraints on model parameters of constant and time-varying dark energy cosmological models, both…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Omer Farooq , Foram Madiyar , Sara Crandall , Bharat Ratra

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 constrain cosmological parameters using only Hubble parameter data and quantify the impact of future Hubble parameter measurements on parameter estimation for the most typical dark energy models. We first constrain cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-27 Jia-Jia Geng , Rui-Yun Guo , Anzhong Wang , Jing-Fei Zhang , Xin Zhang

We present a $f(G,T)$ gravity-based reconstruction of Barrow Holographic Dark Energy (BHDE). This approach extends the conventional HDE model by replacing the Bekenstein-Hawking entropy with Barrow entropy, which encapsulates quantum…

General Relativity and Quantum Cosmology · Physics 2025-05-29 Giuseppe Gaetano Luciano

In Einstein's General Relativity (GR), the gravitational interactions are described by the spacetime curvature. Recently, other alternative geometric formulations and representations of GR have emerged in which the gravitational…

General Relativity and Quantum Cosmology · Physics 2023-08-16 A. Hanin , M. Koussour , Z. Sakhi , M. Bennai

We investigate the viable exponential $f(R)$ gravity in the metric formalism with $f(R)=-\beta R_s (1-e^{-R/R_s})$. The latest sample of the Hubble parameter measurements with 23 data points is used to place bounds on this $f(R)$ model. A…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Yun Chen , Chao-Qiang Geng , Chung-Chi Lee , Ling-Wei Luo , Zong-Hong Zhu