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Related papers: Weyl type $f(Q,T)$ gravity, and its cosmological i…

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We are experiencing a golden age of experimental cosmology, with exact and accurate observations being used to constrain various gravitational theories like never before. Alongside these advancements, energy conditions play a crucial…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-08 Y. Myrzakulov , O. Donmez , M. Koussour , S. Muminov , D. Ostemir , J. Rayimbaev

Non-metricity provides a natural extension of Riemannian geometry, yet its experimental signatures remain largely unexplored. In this work we investigate how spacetime non-metricity can be probed through high-precision observations,…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Mohsen Khodadi , Emmanuel N. Saridakis

To find more deliberate f(R,T) cosmological solutions, we proceed our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

We study the cosmological inflation within the context of f(Q, T) gravity, wherein Q is the nonmetricity scalar and T is the trace of the matter energy-momentum tensor. By choosing a linear combination of Q and T, we first analyze the…

General Relativity and Quantum Cosmology · Physics 2022-08-30 Maryam Shiravand , Saeed Fakhry , Mehrdad Farhoudi

It is argued that a noncommutative geometry of spacetime leads to a reconciliation of electromagnetism and gravitation while providing an underpinning to Weyl's geometry. It also leads to a cosmology consistent with observation. A few other…

General Physics · Physics 2007-05-23 B. G. Sidharth

The $f(Q,C)$ theory, which extends symmetric teleparallel gravity by including the boundary term $C$ in addition to the non-metricity scalar $Q$, provides a unifying framework that encompasses both $f(Q)$ and $f(\mathring{R})$ gravities. In…

General Relativity and Quantum Cosmology · Physics 2025-09-30 Hamid Shabani , Avik De

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 the frameworks of the effective field theory of metric supplemented by some distinct dynamical coordinates parametrized, in turn, by a scalar quartet -- the so-called quartet-metric gravity -- the extension of tensor gravity through a…

General Relativity and Quantum Cosmology · Physics 2019-12-25 Yury F. Pirogov

We show that, in four-dimensional spacetimes with an arbitrary Einstein metric, with and without a cosmological constant, perturbative dynamical degrees of freedom in generic quadratic-curvature gravity can be decoupled into massless and…

General Relativity and Quantum Cosmology · Physics 2019-07-01 Yuki Niiyama , Yuya Nakamura , Ryosuke Zaimokuya , Yu Furuya , Yuuiti Sendouda

We present a complete algebraic classification for the curvature tensor in Weyl-Cartan geometry, by applying methods of eigenvalues and principal null directions on its irreducible decomposition under the group of global Lorentz…

General Relativity and Quantum Cosmology · Physics 2023-08-24 Sebastian Bahamonde , Jorge Gigante Valcarcel

In this study of the modified $f(Q)$ theory of gravity in the spatially flat Friedmann-Lema\^itre-Robertson-Walker (FLRW) spacetime, we explore all the affine connections compatible with the symmetric teleparallel structure; three classes…

General Relativity and Quantum Cosmology · Physics 2024-10-25 Ganesh Subramaniam , Avik De , Tee-How Loo , Yong Kheng Goh

This manuscript endeavors to construct a pilgrim dark energy framework within the $f\mathbb{(Q,T)}$ gravity theory, employing a correspondence approach aligned with a non-interacting model that incorporates pressureless matter alongside a…

General Relativity and Quantum Cosmology · Physics 2025-12-05 M. Sharif , Iqra Ibrar

Weyl gravity in the presence of a non-minimal matter-curvature coupling is presented. Some properties arising from the non-metricity give rise to a second order theory whose vacuum is compatible with a cosmological constant, under…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Cláudio Gomes , Orfeu Bertolami

We construct a Weyl x SU(2)_L x U(1)_Y invariant theory by extending four-dimensional Weyl quadratic gravity with Weyl-invariant scalar, fermion, Yukawa and gauge sectors. The quadratic structure (R^tilde - mu^2 |phi|^2)^2 allows the Weyl…

High Energy Physics - Phenomenology · Physics 2026-05-06 Hao-Qian Peng , Yun-Tao Gu , Yu-Xiao Liu

A `bouncing' cosmological model is proposed in the context of a Weyl-invariant scalar-tensor (WIST) theory of gravity. In addition to being Weyl-invariant the theory is U(1)-symmetric and has a conserved global charge. The entire cosmic…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Meir Shimon

This article deals with a cosmological scenario in $ f(R,T) $ gravity for a flat FLRW model of the universe. We consider the $ f(R,T) $ function as $ f(R)+f(T) $ which starts with a quadratic correction of the geometric term $ f(R) $ having…

General Relativity and Quantum Cosmology · Physics 2022-05-03 Ritika Nagpal , J. K. Singh , A. Beesham , Hamid Shabani

We discuss locally Weyl (scale) covariant generalisation of quadratic curvature gravity theory in three dimensions using Riemann-Cartan-Weyl space-times. We show that this procedure of Weyl gauging yields a consistent generalisation for a…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Tekin Dereli , Cem Yetişmişoğlu

The basic aim of this manuscript is to investigate the cosmological solutions in the context of the modified $f(R, T)$ theory of gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. For our current…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Adnan Malik , Tayyaba Naz , Aimen Rauf , M. Farasat Shamir , Z. Yousaf

We investigate the Weyl space-time extension of general relativity (GR) for studying the FLRW cosmology through focusing and defocusing of the geodesic congruences. We have derived the equations of evolution for expansion, shear and…

General Relativity and Quantum Cosmology · Physics 2011-12-06 Radouane Gannouji , Hemwati Nandan , Naresh Dadhich

In this paper, $f(R,\lm, T)$ gravity is considered. It is a generalization of the theories $f(R,T)$ and $f(R, \lm)$. This modified theory of gravity exhibits strong geometry-matter coupling. The problem of causality and its violation is…

General Relativity and Quantum Cosmology · Physics 2024-11-19 J. S. Gonçalves , A. F. Santos
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