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Related papers: Complete dark energy scenario in $f(Q)$ gravity

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A scalar-tensor theory of gravity is formulated in which $G$ and particle masses are allowed to vary. The theory yields a globally static cosmological model with no evolutionary timescales, no cosmological coincidences, and no flatness and…

General Physics · Physics 2015-10-01 Meir Shimon

The dynamics of perfect fluid as a source in the context of modified gravity, specifically $f(Q,T)$ gravity, are examined within the Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmological model. This gravity is a generic function of the…

General Relativity and Quantum Cosmology · Physics 2024-08-02 S. H. Shekh , Anirudh Pradhan , S. P. Gaikwad , K. R. Mule

The effective evolution of an inhomogeneous universe model in any theory of gravitation may be described in terms of spatially averaged variables. In Einstein's theory, restricting attention to scalar variables, this evolution can be…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Thomas Buchert

We study a correspondence between $f(R)$ model of gravity and a phenomenological kind of dark energy (DE), which is known as QCD ghost dark energy. Since this kind of dark energy is not stable in the context of Einsteinian theory of gravity…

General Physics · Physics 2014-01-21 Kh. Saaidi , Ali. Aghamohammadi , B. Sabet , O. Farooq

A cubic correction of $f(T)$ gravity, where $T$ is the teleparallel scalar torsion, is considered to describe gravity in spatially flat Friedmann-Robertson-Walker model. A scale factor permitting departure from inflation era has been…

General Physics · Physics 2015-11-06 G. G. L. Nashed , W. El Hanafy

In view to scrutinize the idea that nonlocal modifications of General Relativity could dynamically address the dark energy problem, we investigate the evolution of the Universe at infrared scales as an Infinite Derivative Gravity model of…

General Relativity and Quantum Cosmology · Physics 2024-05-03 Salvatore Capozziello , Anupam Mazumdar , Giuseppe Meluccio

This paper aims to develop non-interacting ghost dark energy and generalized ghost dark energy models within the framework of $f(Q)$ theory using the correspondence scheme. We use pressureless matter and a power-law scale factor. The cosmic…

General Relativity and Quantum Cosmology · Physics 2025-07-04 M. Sharif , Madiha Ajmal

All $f(R)$ modified gravity theories are conformally identical to models of quintessence in which matter is coupled to dark energy with a strong coupling. This coupling induces a cosmological evolution radically different from standard…

Astrophysics · Physics 2008-11-26 Luca Amendola , David Polarski , Shinji Tsujikawa

We study the late-time cosmological dynamics of a spatially flat FLRW universe in the framework of $f(Q)$ gravity, where $Q$ denotes the nonmetricity scalar. The matter sector is modeled as a bulk viscous fluid with a free equation-of-state…

General Relativity and Quantum Cosmology · Physics 2026-02-20 Simran Arora , Sai Swagat Mishra , P. K. Sahoo

We investigate the evolution of cosmological perturbations in models of dark energy described by a time-like unit normalized vector field specified by a general function $\mathcal{F}(\mathcal{K})$, so-called Generalized Einstein-Aether…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Richard A. Battye , Francesco Pace , Damien Trinh

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

We present an extension of $f(T)$ gravity, allowing for a general coupling of the torsion scalar $T$ with the trace of the matter energy-momentum tensor $\mathcal{T}$. The resulting $f(T,\mathcal{T})$ theory is a new modified gravity, since…

General Relativity and Quantum Cosmology · Physics 2014-12-12 Tiberiu Harko , Francisco S. N. Lobo , G. Otalora , Emmanuel N. Saridakis

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

Dark energy cosmology is considered in a modified Gauss-Bonnet model of gravity with and without a scalar field. It is shown that these generalizations of General Relativity endow it with a very rich cosmological structure: it may naturally…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Emilio Elizalde , Ratbay Myrzakulov , Valery V. Obukhov , Diego Sáez-Gómez

In this work, we propose a new model that combines holographic dark energy with modified gravity $f(Q,T)$ to explore a possible explanation for the accelerated expansion of the universe. Since there are several tensions of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-08 Xuwei Zhang , Xiaofeng Yang , Yunliang Ren , Shuangnan Chen , Yangjun Shi , Cheng Cheng , Xiaolong He

I briefly outline a new physical interpretation to the average cosmological parameters for an inhomogeneous universe with backreaction. The variance in local geometry and gravitational energy between ideal isotropic observers in bound…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-31 David L. Wiltshire

The accelerated expansion of the universe implies the existence of an energy contribution known as dark energy. Associated with the cosmological constant in the standard model of cosmology, the nature of this dark energy is still unknown.…

General Relativity and Quantum Cosmology · Physics 2022-03-01 Ekim Taylan Hanımeli , Isaac Tutusaus , Brahim Lamine , Alain Blanchard

We construct cosmological model in nonmetricity scalar functional gravitational Lagrangian $f(Q)$ which describes the dynamical evolution of the late accelerating universe. Cosmological models are constructed considering different…

General Relativity and Quantum Cosmology · Physics 2025-04-23 Bikash Chandra Roy , Aroonkumar Beesham , Bikash Chandra Paul

We investigate $f\left( Q\right) $-gravity with a matter-gravity coupling as a geometric dark energy candidate for the description of the late-time cosmic acceleration within a spatially flat Friedmann--Lema\^{\i}tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Andronikos Paliathanasis

A perfect fluid, spatially flat cosmology in a $f(T)$ model, derived from a recently proposed general Born-Infeld type theory of gravity is studied. Four dimensional cosmological solutions are obtained assuming the equation of state…

General Relativity and Quantum Cosmology · Physics 2014-12-04 Soumya Jana