中文
相关论文

相关论文: Dark energy FRW cosmology - dynamical system recon…

200 篇论文

Within the framework of FRW cosmology, we study the QCD modified ghost scalar field models of dark energy in the presence of both interaction and viscosity. For a spatially non-flat FRW universe containing modified ghost dark energy (MGDE)…

综合物理 · 物理学 2013-04-30 K. Karami , S. Asadzadeh , M. Mousivand , Z. Safari

The effective field theory (EFT) of dark energy relies on three functions of time to describe the background dynamics. The viability of these functions is investigated here by means of a thorough dynamical analysis. While the system is…

宇宙学与河外天体物理 · 物理学 2015-06-17 Noemi Frusciante , Marco Raveri , Alessandra Silvestri

In this paper, we consider a recently proposed model of Dark Energy (DE) know as Modified Holographic Ricci DE (MHRDE) (which is function of the Hubble parameter and its first derivative with respect to the cosmic time $t$) in the light of…

综合物理 · 物理学 2017-05-31 Antonio Pasqua , Surajit Chattopadhyay , Iuliia Khomenko

We develop an efficient, non-parametric Bayesian method for reconstructing the time evolution of the dark energy equation of state w(z) from observational data. Of particular importance is the choice of prior, which must be chosen carefully…

宇宙学与河外天体物理 · 物理学 2015-06-03 Robert G. Crittenden , Gong-Bo Zhao , Levon Pogosian , Lado Samushia , Xinmin Zhang

Here, creation of the universe is obtained only from gravity sector. The dynamical universe begins with two basic ingredients (i) vacuum energy, also called dark energy (as vacuum energy is not observed) and (ii) background radiation. These…

高能物理 - 理论 · 物理学 2007-05-23 S. K. Srivastava

We present a geometrical approach that provides a non-perturbative technique, allowing the standard FLRW observer to evaluate a measurable, scale-dependent distance functional between her idealized FLRW past light cone and the actual…

宇宙学与河外天体物理 · 物理学 2026-02-09 Mauro Carfora , Francesca Familiari

The effective evolution of an inhomogeneous universe model in any theory of gravitation may be described in terms of spatially averaged variables. In Einstein's theory, restricting attention to scalar variables, this evolution can be…

广义相对论与量子宇宙学 · 物理学 2010-04-06 Thomas Buchert

In the present research article, we have studied the flat FRW space time with domain wall and holographic dark energy in the context of $f(Q)$ theory of gravity. The exact solutions of the field equations are obtained using two different…

广义相对论与量子宇宙学 · 物理学 2024-10-11 S. P. Hatkar , D. P. Tadas , S. D. Katore

Using the first law of thermodynamics, we propose a relation between the system entropy ($S$) and its IR ($L$) and UV ($\Lambda$) cutoffs. In addition, applying this relation to the apparent horizon of flat FRW universe, whose entropy meets…

综合物理 · 物理学 2018-10-18 H. Moradpour , S. A. Moosavi , I. P. Lobo , J. P. Morais Graça , A. Jawad , I. G. Salako

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

Recent data advances offer the exciting prospect of a first look at whether dark energy has a dynamical equation of state or not. While formally theories exist with a constant equation of state, they are nongeneric -- Einstein's…

天体物理学 · 物理学 2009-11-10 Eric V. Linder , Ramon Miquel

We have studied the effect of dynamical radiation in the interacting barrow holographic dark energy model for a non-flat universe. For both open and closed universes, we have obtained the evolution equation for the energy density parameters…

广义相对论与量子宇宙学 · 物理学 2026-05-08 Gopinath Guin , Souvik Paul , Sunandan Gangopadhyay

Among different candidates to play the role of Dark Energy (DE), modified gravity has emerged as offering a possible unification of Dark Matter (DM) and DE. The purpose of this work is to develop a reconstruction scheme for the modified…

综合物理 · 物理学 2013-11-22 Surajit Chattopadhyay , Antonio Pasqua

We examine the dark energy and matter densities allowed by precision measurements of distances out to various redshifts, in the presence of spatial curvature and (near) arbitrary behavior of the dark energy equation of state. Degeneracies…

宇宙学与河外天体物理 · 物理学 2011-09-22 Arman Shafieloo , Eric V. Linder

A system of effective Einstein equations for spatially averaged scalar variables of inhomogeneous cosmological models can be solved by providing a `cosmic equation of state'. Recent efforts to explain Dark Energy focus on `backreaction…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Thomas Buchert

In this paper, a general FRW cosmological model has been constructed in $f(R,T)$ gravity reconstruction with variable cosmological constant. A number of solutions to the field equations has been generated by utilizing a form for the Hubble…

广义相对论与量子宇宙学 · 物理学 2018-10-17 Nasr Ahmed , Sultan Z. Alamri

In this paper we undertake the modified theory of gravity f(R,T) where R and T are the Ricci scalar and the trace of the energy momentum tensor, respectively. Imposing the conservation of the energy momentum tensor, we obtain a model about…

广义相对论与量子宇宙学 · 物理学 2015-06-30 E. H. Baffou , A. V. Kpadonou , M. E. Rodrigues , M. J. S. Houndjo , J. Tossa

We apply a parametric reconstruction method to a homogeneous, isotropic and spatially flat Friedmann-Robertson-Walker (FRW) cosmological model filled of a fluid of dark energy (DE) with constant equation of state (EOS) parameter interacting…

宇宙学与河外天体物理 · 物理学 2015-05-30 Freddy Cueva Solano , Ulises Nucamendi

In this paper we study the impact of the fractional matter density uncertainty in the reconstruction of the equation of state of dark energy. We consider both standard reconstruction methods, based on the dynamical effect that dark energy…

宇宙学与河外天体物理 · 物理学 2009-11-06 P. P. Avelino

We investigate the corresponding relation between $f(R)$ gravity and an interacting holographic dark energy. By obtaining conditions needed for some observational evidence such as, positive acceleration expansion of universe, crossing the…

宇宙学与河外天体物理 · 物理学 2015-06-04 Kh. Saaidi , A. Aghamohammadi
‹ 上一页 1 8 9 10 下一页 ›