Related papers: Asymmetric Dark Matter in the Shear--dominated Uni…
We study a nonstandard dark-matter thermal history in which strong self-interactions give rise to collective many-body effects at high number density, as in strongly interacting quantum media. At early times, dark matter occupies a…
We demonstrate that if the dark matter (DM) in the Universe contains multiple components,the interactions between the DM components may induce DM conversions. It is then possible that the lightest DM component with an annihilation cross…
We investigate the thermal relic density of a cold dark matter in the brane world cosmology. Since the expansion law in a high energy regime is modified from the one in the standard cosmology, if the dark matter decouples in such a high…
We review the theoretical framework underlying models of asymmetric dark matter, describe astrophysical constraints which arise from observations of neutron stars, and discuss the prospects for detecting asymmetric dark matter.
We study a mechanism where the dark matter number density today arises from asymmetries generated in the dark sector in the early universe, even though total dark matter number remains zero throughout the history of the universe. The dark…
We review the relic density of dark matter in the non-standard cosmological scenarios which includes kination models, brane world cosmology and shear dominated universe. Then we use the Planck data to find constraints on the parameter…
I consider symmetries which could explain observed properties of dark matter, namely, its stability on Gyr time scales or its relic density and discuss how such symmetries can be discovered through the study of the propagation and…
If the early universe is dominated by an energy density which evolves other than radiation-like the normal Hubble-temperature relation $H\propto T^2$ is broken and dark matter relic density calculations in this era can be significantly…
It is a puzzle why the densities of dark matter and dark energy are nearly equal today when they scale so differently during the expansion of the universe. This conundrum may be solved if there is a coupling between the two dark sectors. In…
We show that a nonstandard cosmological history with a period of early matter domination driven by a sub-TeV visible-sector particle can arise rather naturally. This scenario involves a long-lived standard model singlet that acquires a…
We examine a simple dark sector extension where the observed dark matter (DM) abundance arises from a freeze-in process through the decay of heavy vector-like quarks into a scalar dark matter candidate. The detection prospects of such DM…
Dark matter (DM) as a thermal relic of the primordial plasma is increasingly pressured by direct and indirect searches, while the same production mechanism in a decoupled sector is much less constrained. We extend the standard treatment of…
We examine the impact of a faster expanding Universe on the phenomenology of scalar dark matter (DM) associated with $SU(2)_L$ multiplets. Earlier works with radiation dominated Universe have reported the presence of desert region for both…
In some models of thermal relic dark matter, the relic abundance may be set by inelastic scattering processes (rather than annihilations) becoming inefficient as the universe cools down. This effect has been called coscattering. We present…
In recent work we showed that the relic dark matter abundance of QCD axions can be altered when the Peccei-Quinn (PQ) field is coupled to very light scalar/s, rendering the effective axion mass dynamical in the early universe. In this work…
Anisotropic dark energy cosmological models are constructed in the frame work of generalised Brans-Dicke theory with a self interacting potential. Wet dark fluid characterized by a linear equation of state is considered as the source of…
We study the possibility to describe dark matter in a model of the universe with two scale factors and a non-standard Poisson bracket structure characterized by the deformation parameter \kappa. The dark matter evolution is analyzed in the…
This work presents an asymmetric dark matter model with relic density determined by the freeze-out of asymmetric semi-annihilations into long-lived particles slowly decaying into the Standard Model states. We carefully consider the $CPT$…
In models of coupled dark energy and dark matter the mass of the dark matter particle depends on the cosmological evolution of the dark energy field. In this note we exemplify in a simple model the effects of this mass variation on the…
We investigate the thermal relic density of the cold dark matter in the context of the brane world cosmology. Since the expansion law in a high energy regime is modified from the one in the standard cosmology, if the dark matter decouples…