Results 61 to 70 of about 3,373,254 (352)
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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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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Non-adiabatic dark fluid cosmology [PDF]
Journal of Cosmology and Astroparticle Physics, 2009 We model the dark sector of the cosmic substratum by a viscous fluid with an equation of state $p=- $, where $ $ is the fluid-expansion scalar and $ $ is the coefficient of bulk viscosity for which we assume a dependence $ \propto ^ $ on the energy density $ $.
Hipolito-Ricaldi, W.S. +2 more
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Observational constraints and predictions of the interacting dark sector with field-fluid mapping [PDF]
Journal of Cosmology and Astroparticle Physics, 2021 We consider an interacting field theory model that describes the interaction between dark energy-dark matter interaction. Only for a specific interaction term, this interacting field theory description has an equivalent interacting fluid description. For
Joseph P. Johnson +2 more
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Supermassive black holes surrounded by dark matter modeled as anisotropic fluid: epicyclic oscillations and their fitting to observed QPOs [PDF]
, 2021 Recently introduced exact solution of the Einstein gravity coupled minimally to an anisotropic fluid representing dark matter can well represent supermassive black holes in galactic nuclei with realistic distribution of dark matter around the black hole,
Zdenvek Stuchl'ik, J. Vrba
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Dark energy with logarithmic cosmological fluid [PDF]
Journal of the Korean Physical Society, 2014 14 pages, 1 figure, to be published in The Journal of the Korean Physical ...
Phillial Oh, Seyen Kouwn, Seyen Kouwn
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Two-fluid dark matter models [PDF]
Physical Review D, 2011 6 pages, two figures, accepted for publication in ...
Lobo, FSN, Harko, T
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European Physical Journal C: Particles and Fields, 2021 In this paper, we test the weak cosmic censorship conjecture (WCCC) for the Reissner–Nordström–de Sitter (RN-dS) black hole surrounded by perfect fluid dark matter.
Sanjar Shaymatov +2 more
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Galactic halos of fluid dark matter [PDF]
Physical Review D, 2003 Dwarf spiral galaxies - and in particular the prototypical DDO 154 - are known to be completely dominated by an unseen component. The putative neutralinos - so far the favored explanation for the astronomical dark matter - fail to reproduce the well measured rotation curves of those systems because these species tend to form a central cusp whose ...
Arbey, Alexandre +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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