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Related papers: Chameleon dark matter stars

200 papers

Chameleon scalar field is a new model, which introduced to provide a mechanism for exhibiting accelerating universe. Chameleon field has several interesting aspects, such as field dependence on the local matter density. For this model we…

General Physics · Physics 2014-01-21 Kh. Saaidi , H. Sheikhahmadi , J. Afzali

Modified theories of gravity that offer viable models for dark energy often rely on mechanisms that screen their effects in high density environments. From this perspective, it would appear that, once solar system constraints are satisfied,…

General Relativity and Quantum Cosmology · Physics 2020-07-24 Bernardo F. de Aguiar , Raissa F. P. Mendes

If there is a scalar boson field interacting dominantly with a quark or a lepton in the thermal background, its coherent oscillation can be generated through the thermal effect and becomes a good dark matter candidate in a wide range of the…

High Energy Physics - Phenomenology · Physics 2022-01-12 Eung Jin Chun

We consider scenarios where Dark Matter (DM) particles carry baryon and/or lepton numbers, which can be defined if there exist operators connecting the dark to the visible sector. As a result, the DM fields become intimately linked to the…

High Energy Physics - Phenomenology · Physics 2016-09-21 Nicolás Bernal , Chee Sheng Fong , Nayara Fonseca

We study the growth rate of matter perturbations in the context of teleparallel dark energy in a flat universe. We investigate the dynamics of different theoretical scenarios based on specific forms of the scalar field potential. Allowing…

General Relativity and Quantum Cosmology · Physics 2018-12-19 Rocco D'Agostino , Orlando Luongo

Because of their extreme densities and consequently, gravitational potential, compact objects such as neutron stars can prove to be excellent captors of dark matter particles. Considering purely gravitational interactions between dark and…

High Energy Astrophysical Phenomena · Physics 2025-01-22 Pratik Thakur , Anil Kumar , Vivek Baruah Thapa , Vishal Parmar , Monika Sinha

In the Einstein-Cartan gravitational theory with the chameleon field, changing its mass in dependence of a density of its environment, we analyze the Friedmann-Einstein equations for the Universe evolution with the expansion parameter $a$…

General Relativity and Quantum Cosmology · Physics 2020-10-30 A. N. Ivanov , M. Wellenzohn

A coupling between a scalar field (representing the dark energy) and dark matter could produce rich phenomena in cosmology. It affects cosmic structure formation mainly through the fifth force, a velocity-dependent force that acts parallel…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-27 Baojiu Li , John D. Barrow

We investigate the possibility of replacing the cosmological constant with gradual condensation of a scalar field produced during the decay of a superheavy dark matter. The advantage of this class of models to the ordinary quintessence is…

Astrophysics · Physics 2009-11-10 Houri Ziaeepour

We investigate the impact on the classical dynamics of dark matter particles and dark energy of a non-minimal coupling in the dark sector, assuming that the mass of the dark matter particles is coupled to a dark energy scalar field. We show…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-06 P. P. Avelino

We consider the evolution of linear perturbations in models with a nonminimal coupling between dark matter and scalar field dark energy. Growth of matter inhomogeneities in two examples of such models proposed in the literature are…

Astrophysics · Physics 2009-11-11 Tomi Koivisto

Understanding the nature of dark energy and dark matter is one of modern physics' greatest open problems. Scalar-tensor theories with screened scalar fields like the chameleon model are among the most popular proposed solutions. In this…

General Relativity and Quantum Cosmology · Physics 2024-10-16 Ana Lucía Báez-Camargo , Daniel Hartley , Christian Käding , Ivette Fuentes-Guridi

Small-scale clumps of dark matter are gravitationally bounded structures that have masses comparable to or lower than stellar masses and consist of noninteracting or weakly interacting dark matter particles. In this paper, the current…

High Energy Astrophysical Phenomena · Physics 2014-05-12 V. S. Berezinsky , V. I. Dokuchaev , Yu. N. Eroshenko

Composite dark matter is a natural setting for implementing inelastic dark matter - the O(100 keV) mass splitting arises from spin-spin interactions of constituent fermions. In models where the constituents are charged under an axial U(1)…

High Energy Physics - Phenomenology · Physics 2014-11-20 Daniele S. M. Alves , Siavosh R. Behbahani , Philip Schuster , Jay G. Wacker

We show that even a rather minimal extension of the Einstein - Hilbert action by a nonminimal coupling of the scalar field to the Ricci curvature scalar results in configurations that resemble more the dark energy stars then the ordinary…

General Relativity and Quantum Cosmology · Physics 2013-09-02 Dubravko Horvat , Anja Marunovic

We study the effects of dark matter on the structural properties of neutron stars. In particular we investigate how the presence of a dark matter component influences the mass-radius relation, the value of the maximum mass of a neutron star…

High Energy Astrophysical Phenomena · Physics 2025-05-29 Domenico Scordino , Ignazio Bombaci

We show that, as a result of non-linear self-interactions, it is feasible, at least in light of the bounds coming from terrestrial tests of gravity, measurements of the Casimir force and those constraints imposed by the physics of compact…

High Energy Physics - Phenomenology · Physics 2008-11-26 David F. Mota , Douglas J. Shaw

We derive two field theory models of interacting dark energy, one in which dark energy is associated with the quintessence and another in which it is associated with the tachyon. In both, instead of choosing arbitrarily the potential of…

General Relativity and Quantum Cosmology · Physics 2020-07-10 Sandro M. R. Micheletti

We present a quintessence model for the dark energy in which the quintessence scalar field is produced by the decay of a super heavy dark matter and gradually condensate to a classical scalar field. This model can explain both the smallness…

High Energy Physics - Phenomenology · Physics 2009-11-11 Houri Ziaeepour

A model of compact object coupled to inhomogeneous anisotropic dark energy is studied. It is assumed a variable dark energy that suffers a phase transition at a critical density. The anisotropic Lambda-Tolman-Oppenheimer-Volkoff equations…

General Relativity and Quantum Cosmology · Physics 2011-05-12 Cristian R. Ghezzi