English
Related papers

Related papers: Exotic-singularity-driven dark energy

200 papers

In this paper we review in detail a number of approaches that have been adopted to try and explain the remarkable observation of our accelerating Universe. In particular we discuss the arguments for and recent progress made towards…

High Energy Physics - Theory · Physics 2008-11-26 Edmund J. Copeland , M. Sami , Shinji Tsujikawa

We show that the existence of a fundamental length, introduced in Deformed Special Relativity (DSR) inspired minisuper (phase-) space, causes the behavior of the scale factor of the universe to change from that of a universe filled with…

General Relativity and Quantum Cosmology · Physics 2009-11-13 N. Khosravi , H. R. Sepangi

Some analysis of the supernovae type Ia observational data seems to indicate that the Universe today is dominated by a phantom field, for which all energy conditions are violated. Such phantom field may imply a singularity in a future…

Astrophysics · Physics 2008-11-26 J. C. Fabris , S. V. B. Goncalves

An anthropic explanation for evident smallness of the value of the dark energy implies the existence of a time-dependent component of the scalar field, serving, together with a negative-valued cosmological constant, as one of two components…

General Relativity and Quantum Cosmology · Physics 2020-01-08 A. A. Yurova , A. V. Yurov , V. A. Yurov

We investigate exotic stars composed of dark energy within the context of Einstein's General Relativity, by applying an extended Chaplygin gas equation-of-state. To account for anisotropies, we utilize a formalism based on the complexity…

General Relativity and Quantum Cosmology · Physics 2023-02-23 Á. Rincón , G. Panotopoulos , I. Lopes

We discuss whether the future extrapolation of the present cosmological state may lead to a singularity even in case of "conventional" (negative) pressure of the dark energy field, namely $w=p/\rho \geq -1$. The discussion is based on an…

General Relativity and Quantum Cosmology · Physics 2009-11-10 M. Gasperini

Using the fluid representation, we formulate the conditions for the appearance of all four types finite-time future singularity in modified gravity in accelerating FRW universe. It stressed that number of standard quintessence/phantom DE…

High Energy Physics - Theory · Physics 2014-11-20 Shin'ichi Nojiri , Sergei D. Odintsov

We consider a four-dimensional flat-space Friedman universe, which is filled with two interacting ideal fluids (the coupling of dark energy with dark matter of special form). The gravitational equations of motion are solved. It is shown…

High Energy Physics - Theory · Physics 2009-09-07 A. V. Timoshkin

We prove that a homogeneous and isotropic universe containing a scalar field with a power-law potential, $V(\phi )=A\phi ^{n}$, with $0<n<1$ and $A>0$ always develops a finite-time singularity at which the Hubble rate and its first…

General Relativity and Quantum Cosmology · Physics 2015-04-16 John D. Barrow , Alexander A. H. Graham

As first part of this work, experimental information about the decay of isotropic turbulence in ordinary hydrodynamics, u^2(t) proportional to t^{-6/5}, is used as input in FRW equations in order to investigate how an initial fraction f of…

High Energy Physics - Theory · Physics 2011-08-11 Iver Brevik , Olesya Gorbunova , Shin'ichi Nojiri , Sergei D. Odintsov

The background cosmological dynamics of the late Universe is analysed on the framework of a dark energy model described by an holographic Ricci dark energy component. Several kind of interactions between the dark energy and the dark matter…

General Relativity and Quantum Cosmology · Physics 2018-05-09 Mariam Bouhmadi-López , Ahmed Errahmani , Taoufik Ouali , Yaser Tavakoli

A modified Friedmann equation which arises in an extension of general relativity which accommodates a time-dependent fundamental length $L(t)$ leads to cosmological models where the scale factor diverges with an essential singularity at a…

Astrophysics · Physics 2007-05-23 Paul H. Frampton

In this talk we analyze the effect of recently proposed classes of sudden future singularities on causal geodesics of FLRW spacetimes. Geodesics are shown to be extendible and just the equations for geodesic deviation are singular, although…

General Relativity and Quantum Cosmology · Physics 2009-11-13 L. Fernández-Jambrina , R. Lazkoz

Dark energy models which alter the relative scaling behavior of dark energy and matter could provide a natural solution to the cosmic coincidence problem - why the densities of dark energy and dark matter are comparable today. A generalized…

Astrophysics · Physics 2008-11-26 Neal Dalal , Kevork Abazajian , Elizabeth Jenkins , Aneesh V. Manohar

An oscillating universe cycles through a series of expansions and contractions. We propose a model in which ``phantom'' energy with $p < -\rho$ grows rapidly and dominates the late-time expanding phase. The universe's energy density is so…

Astrophysics · Physics 2014-10-13 Matthew G. Brown , Katherine Freese , William H. Kinney

A variety of conditions is considered under which the cosmic dark fluid may be able to develop a future Big Rip or Little Rip singularity. Both one-component and two-component models are considered. In the last-mentioned case we present a…

General Relativity and Quantum Cosmology · Physics 2012-09-25 I. Brevik , R. Myrzakulov , S. Nojiri , S. D. Odintsov

We explore different (and complementary) views of spinors and their exotic counterparts, linking the very existence of the later to the presence of black holes. Moreover, we investigate the effects of the exotic term in the Hawking…

General Relativity and Quantum Cosmology · Physics 2018-11-29 Dino Beghetto , Rogerio T. Cavalcanti , Julio M. Hoff da Silva

The development of dark energy models has stimulated interest to cosmological singularities, which differ from the traditional Big Bang and Big Crunch singularities. We review a broad class of phenomena connected with soft cosmological…

General Relativity and Quantum Cosmology · Physics 2013-08-27 A. Yu. Kamenshchik

We study all four types of finite-time future singularities emerging in late-time accelerating (effective quintessence/phantom) era from $\mathcal{F}(R,G)$-gravity, where $R$ and $G$ are the Ricci scalar and the Gauss-Bonnet invariant,…

High Energy Physics - Theory · Physics 2014-11-20 Kazuharu Bamba , Sergei D. Odintsov , Lorenzo Sebastiani , Sergio Zerbini

We choose a modified Chaplygin Gas Dark energy model for considering some its cosmological behaviors. In this regards, we study different Rip singularity scenarios and bouncing model of the universe in context of this model. We show that by…

General Relativity and Quantum Cosmology · Physics 2014-01-21 S. Davood Sadatian