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Rip Cosmology via Inhomogeneous Fluid
Galaxies, 2013 The conditions for the appearance of the Little Rip, Pseudo Rip and Quasi Rip universes in the terms of the parameters in the equation of state of some dark fluid are investigated. Several examples of the Rip cosmologies are investigated.
Alexander V. Timoshkin +2 more
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Physics Letters B, 2019 The paper brings a novel approach to unification of dark matter and dark energy in terms of a cosmic fluid. A model is introduced in which the cosmic fluid speed of sound squared is defined as a function of its equation of state (EoS) parameter.
Dalibor Perković, Hrvoje Štefančić
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Physics Letters B, 2007 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Dymnikova, Irina, Galaktionov, Evgeny
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Dark radiation from a unified dark fluid model [PDF]
Progress of Theoretical and Experimental Physics, 2014 We present a unified dark fluid model to describe the possible evolutionary behavior of $ N_\mathrm{eff}$ in dark radiation. This model can be viewed as an interacting model for the dark sectors, in which dark matter interacts with dark radiation. We show that the evolution of $ N_\mathrm{eff}$ can be nicely explained without some drawbacks, such as ...
Geng, Chao-Qiang +2 more
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Kerr–Newman-AdS black hole surrounded by perfect fluid matter in Rastall gravity
European Physical Journal C: Particles and Fields, 2018 The Rastall gravity is the modified Einstein general relativity, in which the energy-momentum conservation law is generalized to $$T^{\mu \nu }_{~~;\mu }=\lambda R^{,\nu }$$ T;μμν=λR,ν .
Zhaoyi Xu +3 more
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European Physical Journal C: Particles and Fields, 2020 In this paper, we study the thermodynamic features of a rotating black hole surrounded by perfect fluid dark matter. We analyze the critical behavior of the black hole by considering the known relationship between pressure and cosmological constant.
Seyed Hossein Hendi +3 more
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A viable dark fluid model [PDF]
Astrophysics and Space Science, 2017 We Consider a cosmological model based on a generalization of the equation of state proposed by Nojiri and Odintsov [46] and Štefanči'c [47], [48]. We argue that this model works as a dark fluid model which can interpolate between dust equation of state and the dark energy equation of state.
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Dark energy coupled with dark matter in viscous fluid cosmology [PDF]
Astrophysics and Space Science, 2014 6 pages, no figures; to appear in Astrophys.
Brevik, I. +2 more
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Dark energy and dark matter from an additional adiabatic fluid [PDF]
Physical Review D, 2016 The Dark Sector is described by an additional barotropic fluid which evolves adiabatically during the universe's history and whose adiabatic exponent $ $ is derived from the standard definitions of specific heats. Although in general $ $ is a function of the redshift, the Hubble parameter and its derivatives, we find that our assumptions lead ...
Dunsby, Peter K. S. +2 more
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Darkness without dark matter and energy – generalized unimodular gravity
Physics Letters B, 2017 We suggest a Lorentz non-invariant generalization of the unimodular gravity theory, which is classically equivalent to general relativity with a locally inert (devoid of local degrees of freedom) perfect fluid having an equation of state with a constant ...
A.O. Barvinsky, A.Yu. Kamenshchik
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