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相关论文: Reconstruction of $\Lambda$CDM Universe in $f(Q)$ …

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In this paper, a traversable wormhole in the Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) model with one extra spacelike compact dimension is studied. We have chosen dynamical compactification as the evolution of the fifth dimension. In…

广义相对论与量子宇宙学 · 物理学 2015-06-23 S. Najafi , T. Rostami , S. Jalalzadeh

We consider the field equations for a flat FRW cosmological model, in a generic $f(R)$ gravity model and cast them into a, completely normalized-dimensionless, system of O.D.Es for the scale factor and the function $f(R)$, with respect to…

广义相对论与量子宇宙学 · 物理学 2018-01-24 A. Kuiroukidis

In this work we study the cosmology of the general f(T) gravity theory. We express the modified Einstein equations using covariant quantities, and derive the gauge-invariant perturbation equations in covariant form. We consider a specific…

宇宙学与河外天体物理 · 物理学 2011-11-02 Baojiu Li , Thomas P. Sotiriou , John D. Barrow

We consider the cosmology where some function f(G) of the Gauss-Bonnet term G is added to the gravitational action to account for the late-time accelerating expansion of the universe. The covariant and gauge invariant perturbation equations…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Baojiu Li , John D. Barrow , David F. Mota

We consider non-local modifications of General Relativity given by a distortion function in terms of the inverse of the d'Alembert operator. The inclusion of these terms is motivated by the possibility of reproducing the current accelerated…

广义相对论与量子宇宙学 · 物理学 2023-10-06 Salvatore Capozziello , Rocco D'Agostino

The closed, spatially isotropic FLRW universe (k=+1) is endowed with modifications due to a discrete underlying space-structure. Motivated from Loop Quantum Gravity techniques, a full Thiemann regularisation is performed. The impact of…

广义相对论与量子宇宙学 · 物理学 2021-03-22 Klaus Liegener , Stefan Andreas Weigl

We consider the k=1 Friedman-Lemaitre-Robertson-Walker (FLRW) model within loop quantum cosmology (LQC), from the perspective of the two available quantization prescriptions. We focus our attention on the existence of the so called `inverse…

广义相对论与量子宇宙学 · 物理学 2016-04-28 Alejandro Corichi , Asieh Karami

We propose general f(R,T,R_{\mu\nu}T^{\mu\nu}) theory as generalization of covariant Horava-like gravity with dynamical Lorentz symmetry breaking. FRLW cosmological dynamics for several versions of such theory is considered. The…

广义相对论与量子宇宙学 · 物理学 2015-06-15 Sergei D. Odintsov , Diego Sáez-Gómez

In this paper, we present a cosmological model within the framework of symmetric teleparallel gravity, focusing on $f(Q)$ gravity, where $Q$ represents the non-metricity scalar. Utilizing cosmological datasets, we derive an accelerating…

广义相对论与量子宇宙学 · 物理学 2024-08-09 S. A. Narawade , S. H. Shekh , B. Mishra , Wompherdeiki Khyllep , Jibitesh Dutta

We study the conditions for the consistency of the Friedmann-Robertson-Walker (FRW) metric with the dynamical Chern-Simons modified gravity. It turns out to be that in this situation the accelerated expansion of the Universe takes place,…

高能物理 - 理论 · 物理学 2011-07-14 C. Furtado , J. R. Nascimento , A. Yu. Petrov , A. F. Santos

Classical generalization of general relativity is considered as gravitational alternative for unified description of the early-time inflation with late-time cosmic acceleration. The structure and cosmological properties of number of…

广义相对论与量子宇宙学 · 物理学 2011-07-26 Shin'ichi Nojiri , Sergei D. Odintsov

Following our previous work in [JCAP 1206, 041 (2012)], in this paper, we continue our study of reconstructing $f(R)$ modified gravity models that can be connected to a single scalar field in general relativity via conformal transformation,…

宇宙学与河外天体物理 · 物理学 2015-06-11 Taotao Qiu

For the fourth-order teleparallel $f\left(T,B\right) $ theory of gravity, we investigate the cosmological evolution for the universe in the case of a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker background space. We focus on…

广义相对论与量子宇宙学 · 物理学 2021-06-03 Andronikos Paliathanasis , Genly Leon

In the last few decades, extensions of General Relativity have reached always more attention especially in view of possible breakdowns of the standard $\Lambda$CDM paradigm at intermediate and high redshift regimes. If General Relativity…

广义相对论与量子宇宙学 · 物理学 2020-03-19 Marco Calzà , Alessandro Casalino , Orlando Luongo , Lorenzo Sebastiani

We consider a class of metric f(R) modified gravity theories, analyze them in the context of a Friedmann-Robertson-Walker cosmology and confront the results with some of the known constraints imposed by observations. In particular, we focus…

广义相对论与量子宇宙学 · 物理学 2012-06-11 Luisa G. Jaime , Leonardo Patino , Marcelo Salgado

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…

广义相对论与量子宇宙学 · 物理学 2025-09-30 Hamid Shabani , Avik De

We investigate FLRW cosmology in the framework of symmetric teleparallel $f(Q)$ gravity with a nonminimal coupling between dark matter and the gravitational field. In the noncoincidence gauge, the field equations admit an equivalent…

广义相对论与量子宇宙学 · 物理学 2026-03-26 A. Abebe , P. S. Apostolopoulos , A. Giacomini , G. Leon , F. Moncada , A. Paliathanasis

In this article, we investigate scalar field cosmology in the coincident $f(Q)$ gravity formalism. We calculate the motion equations of $f(Q)$ gravity under the flat Friedmann-Lema\^{i}tre-Robertson-Walker background in the presence of a…

广义相对论与量子宇宙学 · 物理学 2024-04-12 Sayantan Ghosh , Raja Solanki , P. K. Sahoo

We consider f(Q) extended symmetric teleparallel cosmologies, where Q is the non-metricity scalar, and constrain its functional form through the order reduction method. By using this technique, we are able to reduce and integrate the field…

广义相对论与量子宇宙学 · 物理学 2020-12-03 Francesco Bajardi , Daniele Vernieri , Salvatore Capozziello

In this work, we extend previous analyses of the structure formation in the $f(\Box^{-1}R)$ model of nonlocal gravity proposed by Deser and Woodard (DW), which reproduces the background expansion of $\Lambda$CDM with no need of a…

宇宙学与河外天体物理 · 物理学 2017-05-03 Henrik Nersisyan , Adrian Fernandez Cid , Luca Amendola
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