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Related papers: Problems with Propagation and Time Evolution in f(…

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We consider the evolution of cosmological gravitational waves in scalar-tensor theory and $F(R)$ gravity theory as typical models of the modified gravity. Although the propagation speed is not changed from the speed of light, the…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Shin'ichi Nojiri , Sergei D. Odintsov

In Symmetric Teleparallel General Relativity, gravity is attributed to the non-metricity. The so-called "coincident gauge" is usually taken in this theory so that the affine connection vanishes and the metric is the only fundamental…

General Relativity and Quantum Cosmology · Physics 2022-04-12 Dehao Zhao

In the last decade Planck PR4 data together with ground-based experimental data such as, BK18, BAO and CMB lensing, tightened constraint of the tensor to scalar ratio, starting form $r < 0.14$ to $r < 0.032$, while the spectral index lies…

General Relativity and Quantum Cosmology · Physics 2023-08-24 Dalia Saha , Jyoti Prasad Saha , Abhik Kumar Sanyal

The full set of solutions of $f(T)$ gravity with the Minkowski metric is considered in this note. At the 4-th order in perturbations around the trivial tetrad solution, a new mode is found explicitly. Its presence signals a strong coupling…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Jose Beltran Jimenez , Alexey Golovnev , Tomi Koivisto , Hardi Veermae

Symmetric teleparallel gravity and its $f(Q)$ extensions have emerged as promising alternatives to General Relativity (GR), yet the role of explicit geometry-matter couplings remains largely unexplored. In this work, we address this gap by…

General Relativity and Quantum Cosmology · Physics 2025-09-22 Ayush Hazarika , Simran Arora , P. K. Sahoo , Tiberiu Harko

The evolutionary behavior of the Universe has been analysed through the dynamical system analysis in $f(T,B,T_G,B_G)$ gravity, where $T$, $B$, $T_G$, and $B_G$ respectively represent torsion, boundary term, teleparallel Gauss-Bonnet term…

General Relativity and Quantum Cosmology · Physics 2025-01-10 S. A. Kadam , B. Mishra

We study linear cosmological perturbations in the most general teleparallel gravity setting, where gravity is mediated by the torsion and nonmetricity of a flat connection alongside the metric. For a general linear perturbation of this…

General Relativity and Quantum Cosmology · Physics 2023-12-22 Lavinia Heisenberg , Manuel Hohmann

Bianchi I cosmological solutions in f(T) gravity are discussed. We start from diagonal metrics and tetrads and show that their dynamical equations are pretty much tractable analytically, with a possible arena for physical applications. Then…

General Relativity and Quantum Cosmology · Physics 2026-02-24 Alexey Golovnev , Mustafa M. Hemida

In teleparallel gravity, we apply Lorenz type gauge fixing to cope with redundant degrees of freedom in the vierbein field. This condition is mainly to restore the Lorentz symmetry of the teleparallel torsion scalar. In cosmological…

General Relativity and Quantum Cosmology · Physics 2017-07-27 W. El Hanafy , G. G. L. Nashed

It is well known that one cannot apply a conformal transformation to $f(T)$ gravity to obtain a minimally coupled scalar field model, and thus no Einstein frame exists for $f(T)$ gravity. Furthermore nonminimally coupled "teleparallel dark…

General Relativity and Quantum Cosmology · Physics 2016-05-05 Matthew Wright

In this paper, we consider wormhole geometries in the context of teleparallel equivalent of general relativity (TEGR) as well as $f(T)$ gravity. The TEGR is an alternative geometrical formulation of Einstein's general relativity, where…

General Relativity and Quantum Cosmology · Physics 2020-04-15 Ksh. Newton Singh , Ayan Banerjee , Farook Rahaman , M. K. Jasim

In general relativity (GR), the metric tensor of spacetime is essential since it represents the gravitational potential. In other gauge theories (such as electromagnetism), the so-called premetric approach succeeds in separating the purely…

General Relativity and Quantum Cosmology · Physics 2017-04-18 Yakov Itin , Friedrich W. Hehl , Yuri N. Obukhov

Mergers of binary compact objects, accompanied with electromagnetic (EM) counterparts, offer excellent opportunities to explore varied cosmological models, since gravitational waves (GWs) and EM counterparts always carry the information of…

General Relativity and Quantum Cosmology · Physics 2024-01-31 Ran Chen , Yi-Ying Wang , Lei Zu , Yi-Zhong Fan

In this paper, we have explored the field equations of f(T, B) gravity as an extension of teleparallel gravity in an isotropic and homogeneous space time. In the basic formalism developed, the dynamical parameters are derived by…

General Relativity and Quantum Cosmology · Physics 2024-09-27 S. A. Kadam , Jackson Levi Said , B. Mishra

After reminder some facts concerning general relativity ({\bf GR}) we pass to teleparallel gravity. We are confining the special model of the teleparallel gravity, which is popular recently, called {\it the teleparallel equivalent of…

General Relativity and Quantum Cosmology · Physics 2010-11-22 Janusz Garecki

This study aims to investigate the strong gravitational lensing effects in $f(T)$ gravity. We present the theoretical analytic expressions for the lensing effects in $f(T)$ gravity, including deflection angle, magnification, and time delay.…

General Relativity and Quantum Cosmology · Physics 2024-01-12 Xinyue Jiang , Xin Ren , Zhao Li , Yi-Fu Cai , Xinzhong Er

We report new constraints on the parameters of $f(T)$ teleparallel gravity, derived from its imprints on neutrino flavor oscillations. Our analysis reveals that the presence of spacetime torsion can alter both vacuum oscillations and the…

High Energy Physics - Phenomenology · Physics 2026-02-13 H. Yazdani Ahmadabadi , H. Mohseni Sadjadi

In the semi-classical regime, quantum fluctuations embedded in a Riemannian spacetime can be effectively recast as classical back reactions and manifest themselves in the form of non-minimal couplings between matter and curvature. In this…

General Relativity and Quantum Cosmology · Physics 2022-02-07 Che-Yu Chen , Yu-Hsien Kung

Within the framework of modified teleparallel gravity, we reconstruct a f(T) model corresponding to the QCD ghost dark energy scenario. For a spatially flat FRW universe containing only the pressureless matter, we obtain the time evolution…

General Physics · Physics 2014-01-30 K. Karami , A. Abdolmaleki , S. Asadzadeh , Z. Safari

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