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Related papers: Crossing phantom divide in $f(Q)$ gravity

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In this paper, we propose two new models in $f(T)$ gravity to realize universe acceleration and phantom crossing due to dark torsion in the formalism. The model parameters are constrained and the observational test are discussed. The best…

General Physics · Physics 2015-06-03 H. Farajollahi , A. Ravanpak , P. Wu

Symmetric Teleparallel Gravity allows for the reformulation of gravity in the form of nonmetricity by vanishing the contorsion term in the generic affine connection. Our focus is on investigating a recently proposed extension of this theory…

General Relativity and Quantum Cosmology · Physics 2023-12-06 Gaurav N. Gadbail , Avik De , P. K. Sahoo

In this paper, we observationally test the \( f(Q) \) gravity model at both background and perturbation levels using Pantheon$^+$, Hubble measurements, and Redshift Space Distortion Data. We obtain the best-fit parameters by solving…

General Relativity and Quantum Cosmology · Physics 2024-11-08 Dalale Mhamdi , Farida Bargach , Safae Dahmani , Amine Bouali , Taoufik Ouali

The higher-curvature gravity with boundary terms i.e the $f(Q)$ theories, grounded on non-metricity as a fundamental geometric quantity, exhibit remarkable efficacy in portraying late-time universe phenomena. The aim is to delineate…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Pooja Vishwakarma , Parth Shah

We consider a Tsallis holographic dark energy model with interaction between dark energy and matter. The density of dark energy is taken as $\rho_d \sim 3C^2/L^{4-2\gamma}$, where $C$, $\gamma$ are constants. The event horizon is chosen as…

General Relativity and Quantum Cosmology · Physics 2022-05-02 Artyom V. Astashenok , Alexander S. Tepliakov

New high-precision observations are now possible to constrain different gravity theories. To examine the accelerated expansion of the Universe, we used the newly proposed $f(Q,T)$ gravity, where $Q$ is the non-metricity, and $T$ is the…

General Relativity and Quantum Cosmology · Physics 2021-06-30 Simran Arora , Abhishek Parida , P. K. Sahoo

This paper studies the reconstruction criterion in the framework of $f(Q,T)$ gravity using ghost dark energy model, where $Q$ represents the non-metricity and $T$ is the trace of energy-momentum tensor. In this regard, the correspondence…

General Relativity and Quantum Cosmology · Physics 2024-05-09 M. Sharif , Iqra Ibrar

We show that in the exponential $f(T)$ model studied by E. Linder [arXiv:1005.3039, Phys.Rev.D 81, 127301 (2010)], it is impossible to have the crossing of the phantom divide line $w_{\mathrm{DE}}=-1$.

Cosmology and Nongalactic Astrophysics · Physics 2010-08-25 Kazuharu Bamba , Chao-Qiang Geng , Chung-Chi Lee

The recent observations of the Dark Energy Spectroscopic Instrument (DESI) indicated the possibility that the dark energy equation of state parameter $w$ might change from $w<-1$ to $w>-1$ when the redshift $z\sim 0.5$, which is called the…

General Relativity and Quantum Cosmology · Physics 2026-03-10 Shin'ichi Nojiri , Sergei D. Odintsov , V. K Oikonomou

We investigate models of dark energy with purely kinetic multiple k-essence sources that allow for the crossing of the phantom divide line, without violating the conditions of stability. It is known that with more than one kinetic k-field…

Astrophysics · Physics 2010-04-28 Sourav Sur , Saurya Das

We study observational constraints on the modified symmetric teleparallel gravity, the non-metricity $f(Q)$ gravity, which reproduces background expansion of the universe. For this purpose, we use Hubble measurements, Baryonic Acoustic…

General Relativity and Quantum Cosmology · Physics 2021-11-25 Sanjay Mandal , P. K. Sahoo

Recently it has been shown that the cosmological dynamics of covariant $f(Q)$ gravity depend on different affine connections. In this paper, two specific $f(Q)$ models are investigated with SNe+CC+BAO+QSO observational data, and the spatial…

General Relativity and Quantum Cosmology · Physics 2023-10-24 Jiaming Shi

We experience some challenges in general gravitational theory owing to Einstein to explain late time acceleration of universe. To address this issue, geometric components of gravity have been modified in quite a few occasions to have a more…

General Relativity and Quantum Cosmology · Physics 2024-10-04 Santanu Das , Nilanjana Mahata , Priyanka Ray

We consider gravity mediated by non-metricity, with vanishing curvature and torsion. The gravitational action, including an arbitrary function of the non-metric scalar, is investigated in view of characterizing the dark energy effects. In…

General Relativity and Quantum Cosmology · Physics 2022-07-13 Salvatore Capozziello , Rocco D'Agostino

We explore the equation of state (EoS) for dark energy $w_{\mathrm{DE}}$ in modified gravitational theories to explain the current accelerated expansion of the universe. We explicitly demonstrate that the future crossings of the phantom…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Kazuharu Bamba

Recent results from the Dark Energy Spectroscopic Instrument (DESI) provide evidence for a dynamical dark-energy component, whose equation of state appears to have recently crossed the phantom divide. In this Letter, we present an…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-20 E. Abdalla , O. P. F. Piedra , A. A. Escobal , A. M. Vicente , F. B. Abdalla , B. Wang , A. Marins

This paper examines the late-time accelerating Universe and the formation of large-scale structures within the modified symmetric teleparallel gravity framework, specifically using the $f(Q)$-gravity model, in light of recent cosmological…

General Relativity and Quantum Cosmology · Physics 2024-12-31 Shambel Sahlu , Amare Abebe

Cosmology where the effective dark energy crosses $w=-1$ can be realized in Horndeski gravity with shift symmetric terms plus a linear potential. We highlight the special role of the nearly conserved scalar charge. The theory is highly…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Rodrigo Calderon , Eric V. Linder

In this paper we consider FRW cosmology in modified gravity which contain arbitrary functions $f(\phi)$. It is shown that the bouncing solution appears in the model whereas the equation of state (EoS) parameter crosses the phantom divider.…

General Relativity and Quantum Cosmology · Physics 2011-06-09 H. Farajollahi , F. Milani

We study a flat 3-brane in presence of a linear $k$ field with nonzero cosmological constant $\Lambda_{4}$. In this model the crossing of the phantom divide (PD) occurs when the $k$-essence energy density becomes negative. We show that in…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Luis P. Chimento , Monica Forte , Martin G. Richarte
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