Related papers: Ultra-compact spherically symmetric dark matter ch…
We propose the existence of a hidden or dark sector besides the standard model (SM) of particle physics, whose members (both fermionic and bosonic) obey a local SU(2)$_{\rm H}$ gauge symmetry while behaving like a singlet under the SM gauge…
We consider static, spherically symmetric equilibrium configurations consisting of fermionic dark matter nonminimally coupled to dark energy in the form of a quintessence scalar field. With the scalar field coupling function, the form of…
A precise solution of the general relativity equations for centrally symmetric distribution of a pseudoscalar field with U(1) symmetry is presented. It is found that energy density of the field is restricted in the symmetry center and falls…
A simple way of explaining dark matter without modifying known Standard Model physics is to require the existence of a hidden (dark) sector, which interacts with the visible one predominantly via gravity. We consider a hidden sector…
We analyze the most salient cosmological features of axions in extensions of the Standard Model with a gauged anomalous extra U(1) symmetry. The model is built by imposing the constraint of gauge invariance in the anomalous effective…
We propose a framework in which visible matter interacts with matter from a hidden sector through mass mixings of St\"uckelberg U(1) gauge fields. In contrast to other Z' mediation scenarios, our setup has the added appealing features that…
As a candidate for dark matter in galaxies, we study an SU(3) triplet of complex scalar fields which are non-minimally coupled to gravity. In the spherically symmetric static spacetime where the flat rotational velocity curves of stars in…
The theoretical description of compact structures that share some key features with mass varying particles allows for a simple analysis of equilibrium and stability for massive stellar bodies. We investigate static, spherically symmetric…
In this exposition, we seek solutions of the Einstein-Maxwell field equations in the presence of a massive scalar field cast in the Brans-Dicke (BD) formalism which describes charged anisotropic strange stars. The interior spacetime is…
Oscillating ultra-light scalar fields are a natural explanation for the dark matter in our universe, as long as a mechanism, often called a misalignment mechanism, exists to explain the amplitude of the scalar oscillations. If the dark…
The exact solution for a static spherically symmetric field outside a charged point particle is found in a non-linear $U(1)$ gauge theory with a logarithmic Lagrangian. The electromagnetic self-mass is finite, and for a particular relation…
In the effective field theory framework, we consider the effect of supersymmetry breaking via gaugino condensation and supergravity in the hidden sector gauge group on the hidden sector vacuum angle $\theta_h$. The $\theta_h$ parameter…
In the present article authors investigate the anisotropic stellar solutions admitting Finch-Skea symmetry (viable and non-singular metric potentials) in the presence of some exotic matter fields, such as: Bose-Einstein Condensate (BEC)…
An exact, axially symmetric solution to the Einstein-Klein-Gordon field equations is employed to model the dark matter in spiral galaxies. The extended rotation curves from a previous analysis are used to fit the model and a very good…
Recent works by the second author and Maxwell et al. have shown that the Einstein-scalar field conformal constraint equations are highly complex and generally intractable, even in the vacuum case. In this article, to gain a clearer…
We present a new mechanism for cosmic acceleration consisting of a scalar field coupled to a triplet of classical U(1) gauge fields. The gauge fields are arranged in a homogeneous, isotropic configuration, with both electric- and…
A overview is given of the recent developments in the $U(1)_X$ Stueckelberg extensions of the Standard Model and of MSSM where all the Standard Model particles are neutral under the $U(1)_X$ but an axion which is absorbed is charged under…
Large composite dark matter states source a scalar binding field that, when coupled to Standard Model nucleons, provides a potential under which nuclei recoil and accelerate to energies capable of ionization, radiation, and thermonuclear…
In this work we study the boson stars and boson shells in a theory involving massive complex scalar fields coupled to the U(1) gauge field and gravity in a conical potential in the presence of a cosmological constant ${\Lambda}$ which we…
Asymmetric dark matter is a well-motivated approach to explain the apparent coincidence between the relic densities of visible and dark matter, $\Omega_D \simeq 5.4\Omega_b$. A complete explanation requires two components, a relation…