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相关论文: BBN Constraints on $f(Q,T)$ Gravity

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We proposed five $f(Q,T)$ models, which are an extension of symmetric teleparallel gravity, where $Q$ is the non-metricity and $T$ is the trace of the stress-energy tensor. By taking specific values of their parameters, these models have a…

广义相对论与量子宇宙学 · 物理学 2021-11-09 Antonio Nájera , Amanda Fajardo

The non-conservation of the energy-momentum tensor in $f(R,T)$ gravity can be interpreted as an effective manifestation of dissipation. Motivated by this, we propose a new formulation of $f(R,T)$ gravity based on the Herglotz variational…

广义相对论与量子宇宙学 · 物理学 2026-03-20 Marek Wazny , Lehel Csillag , Miguel A. S. Pinto , Tiberiu Harko

We use BBN observational data on primordial abundance of ${}^4He$ to constrain f(T) gravity. The three most studied viable $f(T)$ models, namely the power law, the exponential and the square-root exponential are considered, and the BBN…

宇宙学与河外天体物理 · 物理学 2017-09-20 S. Capozziello , G. Lambiase , E. N. Saridakis

The main objective of this article is to investigate the viability of bouncing cosmological scenarios using different forms of scale factors with perfect matter configuration in the framework of extended symmetric teleparallel theory. This…

广义相对论与量子宇宙学 · 物理学 2024-07-31 M. Zeeshan Gul , M. Sharif , Shamraiza Shabbir

$f(T,B)$ teleparallel gravity is a recently proposed straightforward generalization of the popular $f(T)$ teleparallel gravity by the incorporation of a boundary term $B=\frac{2}{e}\partial_{i}(e T ^{i}) = \bigtriangledown_{i}T^{i}$ where…

广义相对论与量子宇宙学 · 物理学 2020-08-25 Snehasish Bhattacharjee

We propose a novel cosmological framework within the $f(R,T)$ type modified gravity theory, incorporating a non-minimally coupled with the higher order of the Ricci scalar ($R$) as well as the trace of the energy-momentum tensor ($T$).…

广义相对论与量子宇宙学 · 物理学 2024-02-06 Shaily , Akanksha Singh , J. K. Singh , Saibal Ray

$f(Q,T)$ theory of gravity is very recently proposed to incorporate within the action Lagrangian, the trace $T$ of the energy-momentum tensor along with the non-metricity scalar $Q$. The cosmological application of this theory in a…

广义相对论与量子宇宙学 · 物理学 2023-05-24 Tee-How Loo , M. Koussour , Avik De

The variety of theories that can account for the dark energy phenomenon encourages current research to concentrate on a more in-depth examination of the potential impacts of modified gravity on both local and cosmic scales. We discuss some…

广义相对论与量子宇宙学 · 物理学 2023-01-27 Gaurav N. Gadbail , Simran Arora , P. K. Sahoo

This article presents cosmological models that arise in a subclass of $f(R,T)=f(R)+f(T)$ gravity models, with different $f(R)$ functions and fixed $T$-dependence. That is, the gravitational lagrangian is considered as $f(R,T)=f(R)+\lambda…

广义相对论与量子宇宙学 · 物理学 2018-09-18 P. K. Sahoo , P. H. R. S. Moraes , Parbati Sahoo , Binaya K. Bishi

We study $f(R,T)$ gravity, in which the curvature $R$ appearing in the gravitational Lagrangian is replaced by an arbitrary function of the curvature and the trace $T$ of the stress-energy tensor. We focus primarily on situations where $f$…

广义相对论与量子宇宙学 · 物理学 2019-10-02 Sarah B. Fisher , Eric D. Carlson

In this paper, a cosmological model of the Universe is presented in $f(Q,T)$ gravity and the parameters are constrained by cosmological data sets. Initially, a generalised form of $f(Q,T)$ model is used as $f(Q,T)=-\lambda_{1}…

广义相对论与量子宇宙学 · 物理学 2024-03-21 A. S. Agrawal , B. Mishra , S. K. Tripathy

We study the $f(Q,T)$ gravity in the framework of Weyl geometry (known as Weyl-type $f(Q,T)$ gravity), where $Q$ denotes the non-metricity scalar, and $T$ denotes the energy-momentum tensor trace. In this work, we consider the $f(Q,T)$…

广义相对论与量子宇宙学 · 物理学 2024-11-04 Gaurav N. Gadbail , Himanshu Chaudhary , Amine Bouali , P. K. Sahoo

This study proposes a unified framework comprising two complementary approaches to constrain three functional forms of $f(T,B)$ gravity, namely the linear, quadratic, and general power law models, by jointly utilizing early and late…

宇宙学与河外天体物理 · 物理学 2026-01-07 Yahia Al-Omar , Majida Nahili , Nidal Chamoun , Marwan Al-Raeei

In this work, we study the f(Q,T) model of symmetric teleparallel modified gravity in the framework of cosmological perturbation theory. Using a general approach, we extract the differential matter density equation then we simplify it as a…

广义相对论与量子宇宙学 · 物理学 2025-08-06 Houda Filali , Rachid Ahl Laamara , Mohamed Bennai , El Hassan Saidi

We consider f(R,T) modified theories of gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar R and of the trace of the stress-energy tensor T. We obtain the gravitational field equations in the…

广义相对论与量子宇宙学 · 物理学 2011-07-14 Tiberiu Harko , Francisco S. N. Lobo , Shin'ichi Nojiri , Sergei D. Odintsov

We investigate the logarithmic form of $f(Q,T)$ gravity with two different choices of matter Lagrangian such as: $\mathcal{L}_m = p$ and $\mathcal{L}_m = -\rho$. The parameters of the model has been constrained using Cosmic Chronometers…

广义相对论与量子宇宙学 · 物理学 2025-09-18 Rahul Bhagat , I. V. Fomin , B. Mishra

In this work, we investigate Big Bang Nucleosynthesis (BBN) within the framework of $f(T,{L}_m)$ gravity, where the gravitational Lagrangian is generalized as a function of the torsion scalar $T$ and the matter Lagrangian ${L}_m$. We…

宇宙学与河外天体物理 · 物理学 2025-09-25 Daniel F. P. Cruz , David S. Pereira , Francisco S. N. Lobo , José P. Mimoso

In this paper, we investigate the cosmological implications and constraints of Weyl-type $f(Q, T)$ gravity. This theory introduces a coupling between the non-metricity $Q$ and the trace $T$ of the energy-momentum tensor, using the…

广义相对论与量子宇宙学 · 物理学 2024-03-27 Alnadhief H. A. Alfedeel , M. Koussour , N. Myrzakulov

This study delves into modified gravity theories that are equivalent to General Relativity but involve the torsion or non-metricity scalar instead of the curvature scalar. Specifically, we focus on $f(Q,T)$ gravity, which entails an…

广义相对论与量子宇宙学 · 物理学 2023-11-22 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , H. M. Elkhair

In this article, we study the expanding nature of universe in the contest of $f(R,L_m)$ gravity theory, here $ R $ represents the Ricci scalar and $ L_m $ is the matter Lagrangian density. With a specific form of $ f(R,L_m) $, we obtain the…

广义相对论与量子宇宙学 · 物理学 2023-06-28 J. K. Singh , Shaily , Ratbay Myrzakulov , Harshna Balhara