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相关论文: A dynamical system representation of generalized R…

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We systematically review some standard issues and also the latest developments of modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time acceleration era. Particularly, we present the formalism of standard…

广义相对论与量子宇宙学 · 物理学 2021-05-25 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

The observed acceleration of the Universe can be explained by modifying general relativity. One such attempt is the nonlocal model of Deser and Woodard. Here we fix the background cosmology using results from the Planck satellite and…

宇宙学与河外天体物理 · 物理学 2014-09-05 Scott Dodelson , Sohyun Park

This study conducts a meticulous examination of the cosmological implications inherent in Rastall gravity and $f(R)$ gravity models, assessing their efficacy across distinct cosmic epochs, from early universe structure formation to…

广义相对论与量子宇宙学 · 物理学 2025-01-14 Muhammad Yarahmadi , Amin Salehi , Hadis Mousavi

The expansion of the Universe is accelerating, as testified by observations of supernovae of type Ia as a function of redshift. Explanations are of two types: modifications of Einstein gravity or new forms of energy, coined dark energy.The…

天体物理学 · 物理学 2007-05-23 Matts Roos

We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of General Relativity (GR) has been tested accurately…

宇宙学与河外天体物理 · 物理学 2016-03-24 Kazuya Koyama

We investigate the cosmic dynamics of Rastall gravity in non-flat Friedmann-Robertson-Walker (FRW) space-time with barotropic fluid. In this context, we are concerned about the class of model satisfying the affine equation of state. We…

广义相对论与量子宇宙学 · 物理学 2022-07-27 Ashutosh Singh , Gyan Prakash Singh , Anirudh Pradhan

The discovery of cosmic acceleration has raised the intriguing possibility that we are witnessing the first breakdown of General Relativity on cosmological scales. In this article I will briefly review current attempts to construct a…

广义相对论与量子宇宙学 · 物理学 2015-05-28 Mark Trodden

The stable critical points and their corresponding cosmology are derived in the teleparallel gravity with an added Gauss-Bonnet topological invariant term. We have analyzed the dynamics of the Universe by presenting two cosmological viable…

广义相对论与量子宇宙学 · 物理学 2023-12-12 S. A. Kadam , Santosh V Lohakare , B. Mishra

In this study, we explore the cosmological evolution of the Universe in the framework of covariant $f(Q)$ gravity, with a coupling function that evolves dynamically in proportion to the Hubble parameter. Two specific forms of the function…

广义相对论与量子宇宙学 · 物理学 2026-04-29 S. A. Narawade , S. A. Kadam

Recently, the Dark Energy Spectroscopic Instrument (DESI) collaboration has presented results indicating that dark energy may exhibit dynamical behavior. Calibrated gamma-ray burst (GRB) correlations can be employed to verify or reject a…

宇宙学与河外天体物理 · 物理学 2026-04-03 Marco Muccino , Massimo Della Valle , Luca Izzo , Orlando Luongo

In this work, we investigate static configurations of dark energy stars within the framework of Rastall-Rainbow (R-R) gravity, which combines an energy-dependent deformation of spacetime with a nonminimal coupling between matter and…

广义相对论与量子宇宙学 · 物理学 2025-10-21 Ayan Banerjee , Bobur Turimov , Sulton Usanov , Murodbek Vapaev , Yunus Turaev , Zebo Avezmuratova

It has been shown that in the context of General Relativity (GR) enriched with a new set of discrete symmetry reversal conjugate metrics, negative energy states can be rehabilitated while avoiding the well-known instability issues. We…

广义相对论与量子宇宙学 · 物理学 2016-08-16 Frederic Henry-Couannier , André Tilquin , Anne Ealet , Charling Tao

Taking up four model universes we study the behaviour and contribution of dark energy to the accelerated expansion of the universe, in the modified scale covariant theory of gravitation. Here, it is seen that though this modified theory may…

广义相对论与量子宇宙学 · 物理学 2020-01-28 Koijam Manihar Singh , Sanjay Mandal , Longjam Parbati Devi , P. K. Sahoo

In this paper, we perform the dynamical system analysis of the cosmological models framed in the extended teleparallel gravity, the $f (T, B)$ gravity. We use the mapping, $f(T, B)$ $\rightarrow$-$T$+$\tilde{f}(T, B)$, and define the…

广义相对论与量子宇宙学 · 物理学 2023-09-13 S. A. Kadam , Ninaad P. Thakkar , B. Mishra

We propose a covariant formulation of refracted gravity (RG), a classical theory of gravity based on the introduction of gravitational permittivity (GP), a monotonic function of the local mass density, in the standard Poisson equation. GP…

宇宙学与河外天体物理 · 物理学 2023-06-30 Andrea Pierfrancesco Sanna , Titos Matsakos , Antonaldo Diaferio

The reason for the present accelerated expansion of the Universe stands as one of the most profound questions in the realm of science, with deep connections to both cosmology and fundamental physics. From a cosmological point of view,…

广义相对论与量子宇宙学 · 物理学 2024-08-22 Peixiang Ji , Lijing Shao

The recently introduced relativistic Lagrangian darkon fluid model (EPJ C (2015) 75:9) is generalized to a self-gravitating, irrotational, pressure-less and stress free geodesic fluid, whose energy-momentum tensor is dust-like with…

综合物理 · 物理学 2016-04-18 Peter C. Stichel

The generalized Chaplygin gas (GCG) model allows for an unified description of the cosmologically recent accelerated expansion of the Universe and of the evolution of energy density perturbations. This dark energy - dark matter unification…

天体物理学 · 物理学 2007-05-23 O. Bertolami

Observations provide increasingly strong evidence that the universe is accelerating. This revolutionary advance in cosmological observations confronts theoretical cosmology with a tremendous challenge, which it has so far failed to meet.…

天体物理学 · 物理学 2008-11-26 Ruth Durrer , Roy Maartens

In this paper, we investigate and analyze the cosmological dynamics of the universe, with an effect of modified $f(R)$ gravity emerging at cosmological scale. We choose the Einstein frame as a physical frame. We consider phase portraits of…

天体物理学 · 物理学 2007-05-23 Daris Samart