Related papers: Cosmological Constraints on Scalar Field Dark Matt…
The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…
We examine how the properties of dark matter, parameterised by an equation of state parameter $w$ and two perturbative Generalised Dark Matter (GDM) parameters $c^2_s$ (the sound speed) and $c^2_\text{vis}$ (the viscosity), are constrained…
Six challenges for the standard cosmological model $\Lambda$CDM are listed, which arise when comparing theoretical predictions with observational data on scales of ~1 Mpc. Different parameters of luminous and dwarf galaxies in the local…
The Scalar Field Dark Matter (SFDM) model, also called Fuzzy, Wave, Bose-Einstein, Ultra-light Dark Matter, has received a lot of attention because it has been able to provide simpler and more natural explanations for various features of…
(Abridged) Despite the success of Cold Dark Matter (CDM) in explaining a wide range of observations, the microscopic nature of dark matter is still unknown. Attempts to detect WIMPs, the most commonly studied form, have not yet succeeded.…
Atomic dark matter is a simple but highly theoretically motivated possibility for an interacting dark sector that could constitute some or all of dark matter. We perform a comprehensive study of precision cosmological observables on minimal…
Fuzzy dark matter (FDM) is an attractive dark matter candidate motivated by small scale problems in astrophysics and with a rich phenomenology on those scales. We scrutinize the FDM model, more specifically the mass of the FDM particle,…
We calculate the pair-annihilation cross section of real scalar singlet dark matter into two mono-energetic photons. We derive constraints on the theory parameter space from the Fermi limits on gamma-ray lines, and we compare with current…
Scalar fields aptly describe equation of state of dark energy. The scalar field models were initially proposed to circumvent the fine tuning problem of cosmological constant. However, the model parameters also need a fine tuning of their…
Cosmological dark matter in the form of neutrinos with masses of up to a few electron volts is known as hot dark matter. After an historical review of the subject, this article considers constraints on hot dark matter from current data on…
Future sattelite, balloon and ground based experiments will give precision determinations of the basic cosmological parameters and hence determine the amount of cold dark matter accurately. We consider here two cosmological models, the…
We study static configurations of dark matter coupled to a scalar field responsible for the dark energy of the Universe. The dark matter is modelled as a Fermi gas within the Thomas-Fermi approximation. The mass of the dark matter particles…
As one of the fundamental unknowns of our Universe, the mass of dark matter remains to be a topic of great interest. We consider the possibility of a time-variation of the dark matter mass. We study the cosmological constraints on a model…
In the framework of an nonuniversal $U(1)'$ extension of the standard model, we propose an scalar candidate for cold dark matter which exhibits interactions with ordinary matter through Higgs and gauge bosons. Using limits from low energy…
In this paper, we propose a modified scale factor (MSF) that allows us to explore the accelerating expansion of the universe without invoking the traditional dark-energy model, as described in the Lambda cold dark matter ($\Lambda$CDM)…
In this study, we have explored a scalar field cosmological model in the axially symmetric Bianchi type-I universe. In this study, our aim is to constrain the scalar field dark energy model in an anisotropic background. For this purpose,…
The existence and detection of scalar fields could provide solutions to long-standing puzzles about the nature of dark matter, the dark compact objects at the centre of most galaxies, and other phenomena. Yet, self-interacting scalar fields…
We discover that the mass of dark matter particles mDM is imprinted in phase-correlations of the cosmic density field more significantly than in the 2-point correlation. In particular, phase-correlations trace mDM out to scales about five…
After the observation in 2012 of a new scalar particle closely resembling the Higgs boson of the Standard Model of particle physics, there is a general consensus that there must be Physics Beyond the Standard Model, with present experiments…
We study the dynamics of the scalar field FLRW flat cosmological models within the framework of the Unified Dark Matter (UDM) scenario. In this model we find that the main cosmological functions such as the scale factor of the Universe, the…