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Can dark matter be a scalar field? [PDF]
Journal of Cosmology and Astroparticle Physics, 2016 In this paper we study a real scalar field as a possible candidate to explain the dark matter in the universe. In the context of a free scalar field with quadratic potential, we have used Union 2.1 SN Ia observational data jointly with a Planck prior over the dark matter density parameter to set a lower limit on the dark matter mass as $m\geq0.12H_0 ...
Jesus, J. F. +3 more
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Scalar-field theory of dark matter [PDF]
International Journal of Modern Physics A, 2014 We develop a theory of dark matter based on a previously proposed picture, in which a complex vacuum scalar field makes the universe a superfluid, with the energy density of the superfluid giving rise to dark energy, and variations from vacuum density giving rise to dark matter. We formulate a nonlinear Klein–Gordon equation to describe the superfluid,
Xiaofei Zhao, Kerson Huang, Chi Xiong
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UNIFIED DARK MATTER IN SCALAR FIELD COSMOLOGIES [PDF]
Modern Physics Letters A, 2007 Considering the general Lagrangian of k-essence models, we study and classify them through variables connected to the fluid equation of state parameter wκ. This allows one to find solutions around which the scalar field describes a mixture of dark matter and cosmological constant-like dark energy, an example being the purely kinetic model proposed by ...
BERTACCA, DANIELE +2 more
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Parkes Pulsar Timing Array constraints on ultralight scalar-field dark matter [PDF]
Physical Review D, 2018 It is widely accepted that dark matter contributes about a quarter of the critical mass-energy density in our Universe. The nature of dark matter is currently unknown, with the mass of possible constituents spanning nearly one hundred orders of magnitude.
N. Porayko +29 more
semanticscholar +1 more source
Scalar field dark matter: helping or hurting small-scale problems in cosmology? [PDF]
Monthly notices of the Royal Astronomical Society, 2018 Building upon results of cosmological simulations of ultra-light scalar field dark matter (SFDM), we present a comprehensive model for the density profiles of SFDM haloes as a function of halo virial mass $M_{\rm h}$ and scalar field mass $m$.
V. Robles, J. Bullock, M. Boylan-Kolchin
semanticscholar +1 more source
Scalar field dark matter spectator during inflation: the effect of self-interaction [PDF]
Journal of Cosmology and Astroparticle Physics, 2019 Nowadays cosmological inflation is the most accepted mechanism to explain the primordial seeds that led to the structure formation observed in the Universe.
Luis E. Padilla +3 more
semanticscholar +1 more source
Halos of unified dark matter scalar field [PDF]
Journal of Cosmology and Astroparticle Physics, 2008 We investigate the static and spherically symmetric solutions of Einstein's equations for a scalar field with non-canonical kinetic term, assumed to provide both the dark matter and dark energy components of the Universe. In particular, we give a prescription to obtain solutions (dark halos) whose rotation curve v_c(r) is in good agreement with ...
BERTACCA, DANIELE +2 more
openaire +3 more sources
Universe, 2020 The generalized hybrid metric-Palatini theory of gravity admits a scalar-tensor representation in terms of two interacting scalar fields. We show that, upon an appropriate choice of the interaction potential, one of the scalar fields behaves like dark ...
Paulo M. Sá
doaj +1 more source
Stability of Cauchy horizon in a charged de-Sitter spacetime with dark matter
European Physical Journal C: Particles and Fields, 2023 The violation of strong cosmic censorship (SCC) in RNdS black holes by a minimally coupled neutral massless scalar field has recently been discovered. This paper investigates the stability of the Cauchy horizon of a spherically charged de-Sitter black ...
Xue-Ying Nan, Jia Tan, Jie Jiang
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Dark sector impact on gravitational collapse of an electrically charged scalar field [PDF]
, 2015 Dark matter and dark energy are dominating components of the Universe. Their presence affects the course and results of processes, which are driven by the gravitational interaction.
Nakonieczna, Anna +2 more
core +2 more sources