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相关论文: Loop Quantum Cosmology Matter Bounce Reconstructio…

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This study explores the bouncing solutions within the framework of modified $f(Q, L_m)$ gravity. We examine four prominent bouncing models, the symmetric bounce, super bounce, oscillatory bounce, and matter bounce, each of which has been…

广义相对论与量子宇宙学 · 物理学 2026-04-28 S. A. Kadam , V. A. Kshirsagar , Santosh Kumar Yadav

We derive an exact $f(T)$ gravity in the absence of ordinary matter in Friedmann-Robertson-Walker (FRW) universe, where $T$ is the teleparallel torsion scalar. We show that vanishing of the energy-momentum tensor $\mathcal{T}^{\mu \nu}$ of…

高能物理 - 理论 · 物理学 2016-10-19 W. El Hanafy , G. L. Nashed

In this work, we analyse the late-time evolution of the universe for a particular $f(R)$ gravity model built from an exponential function of the scalar curvature. Following the literature, we write the field equations in terms of a suited…

广义相对论与量子宇宙学 · 物理学 2023-10-18 A. Oliveros , Mario A. Acero

The cosmological reconstruction scheme for modified $F(R)$ gravity is developed in terms of e-folding (or, redshift). It is demonstrated how any FRW cosmology may emerge from specific $F(R)$ theory. The specific examples of well-known…

高能物理 - 理论 · 物理学 2014-11-20 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Saez-Gomez

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

In this paper, we use genetic algorithms, a specific machine learning technique, to achieve a model-independent reconstruction of $f(T)$ gravity. By using $H(z)$ data derived from cosmic chronometers and radial Baryon Acoustic Oscillation…

宇宙学与河外天体物理 · 物理学 2025-06-09 Redouane El Ouardi , Amine Bouali , Imad El Bojaddaini , Ahmed Errahmani , Taoufik Ouali

Modified $f(R)$ gravity in the Palatini approach has been presently applied to Cosmology as a realistic alternative to dark energy. In this concern, a number of authors have searched for observational constraints on several $f(R)$ gravity…

天体物理学 · 物理学 2009-06-23 F. C. Carvalho , E. M. Santos , J. S. Alcaniz , J. Santos

We discuss the possibility that suitable modifications of gravity could account for some amount of the radiation we observe today, in addition to the possibility of explaining the present speed up of the universe. We start introducing and…

广义相对论与量子宇宙学 · 物理学 2015-12-02 Joao Morais , Mariam Bouhmadi-Lopez , Salvatore Capozziello

Modified gravity has attracted much attention over the last few years and remains a potential candidate for dark energy. In particular, the so-called viable f(R) gravity theories, which are able to both recover General Relativity (GR) and…

广义相对论与量子宇宙学 · 物理学 2016-04-20 Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby , Sulona Kandhai , Diego Saez-Gomez

In this short review, we revisit inflation in F(R)-gravity. We find several F(R)-models for viable inflation by applying some reconstruction techniques. A special attention is payed in the reproduction of the last Planck satellite data. The…

广义相对论与量子宇宙学 · 物理学 2016-09-02 Lorenzo Sebastiani , Ratbay Myrzakulov

Here, we peruse cosmological usage of the most promising candidates of dark energy in the framework of f(R) theory. We reconstruct the different f(R) modified gravity models in the spatially flat FRW universe according to the ordinary and…

广义相对论与量子宇宙学 · 物理学 2011-07-18 K. Karami , M. S. Khaledian

Some bouncing models are investigated in the framework of an extended theory of gravity. The extended gravity model is a simple extension of the General Relativity where an additional matter geometry coupling is introduced to account for…

广义相对论与量子宇宙学 · 物理学 2021-06-10 S K Tripathy , B Mishra , Saibal Ray , Rikpratik Sengupta

In this work, we consider four $f(R)$ gravity models -- the Hu-Sawicki, Starobinsky, Exponential and Tsujikawa models -- and use a range of cosmological data, together with Markov Chain Monte Carlo sampling techniques, to constrain the…

宇宙学与河外天体物理 · 物理学 2022-01-05 Christine R. Farrugia , Joseph Sultana , Jurgen Mifsud

In this paper, we have studied the bouncing behavior of the cosmological models formulated at the background of the Hubble function in the F(R, G) theory of gravity, where R and G denote the Ricci scalar and Gauss-Bonnet invariant. The…

广义相对论与量子宇宙学 · 物理学 2022-12-02 Santosh V Lohakare , Francisco Tello-Ortiz , S. K. Tripathy , B. Mishra

We review on the viability of $F(R)$-gravity. We show that recent cosmic acceleration, radiation/matter-dominated epoch and inflation could be realized in the framework of $F(R)$-gravity in the unified way. For some classes of…

天体物理学 · 物理学 2008-02-01 Shin'ichi Nojiri , Sergei D. Odintsov

We present a novel reconstruction method of $f(T)$ teleparallel gravity from phenomenological parameterizations of the deceleration parameter or other alternatives. This can be used as a toolkit to produce viable modified gravity scenarios…

广义相对论与量子宇宙学 · 物理学 2019-10-29 W. El Hanafy , G. G. L. Nashed

We analyze the cosmological implementation of Palatini $f(R)$ theories, constructed with a Nieh-Yan term and solved with respect to the torsion. We consider the relevant case of the quadratic correction to the Hilbert-Palatini action in the…

广义相对论与量子宇宙学 · 物理学 2019-05-21 Flavio Bombacigno , Giovanni Montani

We propose the reconstruction of $F(R)$ gravity in such a way that corresponding theory admits cyclic and ekpyrotic universe solutions. The number of explicit examples of such $F(R)$ model is found. The comparison with the reconstructed…

高能物理 - 理论 · 物理学 2015-05-30 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Saez-Gomez

We study the emergence of cosmic hysteresis in cyclic bouncing universes within the framework of analytically reconstructed $f(R)$ gravity. Using exact bouncing scale factor solutions of exponential and power-law forms, we reconstruct the…

广义相对论与量子宇宙学 · 物理学 2025-08-15 Aritra Sanyal , Praveen Kumar Dhankar , Albert Munyeshyaka , Safiqul Islam , Farook Rahaman

We develop the reconstruction program for the number of modified gravities: scalar-tensor theory, $f(R)$, $F(G)$ and string-inspired, scalar-Gauss-Bonnet gravity. The known (classical) universe expansion history is used for the explicit and…

高能物理 - 理论 · 物理学 2010-04-06 Shin'ichi Nojiri , Sergei D. Odintsov