Related papers: Is the Dark Matter a Solid?
The possibility of dark matter being a dissipative component represents an option for the standard view where cold dark matter (CDM) particles behave on large scales as an ideal fluid. By including a physical mechanism to the dark matter…
In a recent paper (arXiv:1106.4546), we introduced "dynamical dark matter," a new framework for dark-matter physics, and outlined its underlying theoretical principles and phenomenological possibilities. Unlike most traditional approaches…
Current dark matter detection strategies are based on the assumption that the dark matter is a gas of non-interacting particles with a reasonably large number density. This picture is dramatically altered if there are significant self…
The dark energy-cold dark matter paradigm ($\Lambda$CDM) has gained widespread acceptance because it explains the pattern of anisotropies observed in the cosmic microwave background radiation, the observed distribution of large scale…
Is Dark Matter part of a Dark Sector? The possibility of a dark sector neutral under Standard Model (SM) forces furnishes an attractive explanation for the existence of Dark Matter (DM), and is a compelling new-physics direction to explore…
We explore a cosmological model in which dark matter is non-minimally coupled to gravity at the fluid level. While typically subdominant compared to Standard Model forces, such couplings may dominate dark matter dynamics. We show that this…
The gravitational field of an isolated, axisymmetric flat disk of spinning dust is calculated approximately in the weak-field limit of quasi-metric gravity. Boundary conditions single out the exponential disk as a "preferred" physical…
The traditional "explanation" for the observed acceleration of the universe is the existence of a positive cosmological constant. However, this can hardly be a truly convincing explanation, as an expanding universe is not expected to have a…
An overview is presented of a recently proposed "radically conservative" solution to the problem of dark energy in cosmology. The proposal yields a model universe which appears to be quantitatively viable, in terms of its fit to supernovae…
The nature of the main constituents of the mass of the universe is one of the outstanding riddles of cosmology and astro-particle physics. Current models explaining the evolution of the universe, and measurements of the various components…
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…
The nonbaryonic dark matter of the Universe is assumed to consist of new stable forms of matter. Their stability reflects symmetry of micro world and particle candidates for cosmological dark matter are the lightest particles that bear new…
A comet-like, but magnitudes smaller, extremely low albedo interstellar meteoroid population of fragile aggregates with solar type composition, measured in space and terrestrially, is most probably the universal dark matter. Although…
We discuss a cosmology in which cold dark-matter particles decay into relativistic particles. We argue that such decays could lead naturally to a bulk viscosity in the cosmic fluid. For decay lifetimes comparable to the present hubble age,…
We revisit a cosmological model where dark matter (DM) and dark energy (DE) follow barotropic equations of state, allowing deviations from the standard $\Lambda$CDM framework (i.e. $w_{dm} \neq 0$, $w_{de} \neq -1$), considering both flat…
We find that current Cosmic Microwave Background (CMB) anisotropy data strongly constrain the mean spatial curvature of the Universe to be near zero, or, equivalently, the total energy density to be near critical-as predicted by inflation.…
The structure and evolution of Primordial Antimatter domains and Dark matter objects are analysed. Relativistic low-density antimatter domains are described. The Relativistic FRW perfect-fluid solution is found for the characterization of…
The two dark sectors of the universe - dark matter and dark energy - may interact with each other. Background and linear density perturbation evolution equations are developed for a generic coupling. We then establish the general conditions…
The existence of cosmological dark matter is in the bedrock of the modern cosmology. The dark matter is assumed to be nonbaryonic and to consist of new stable particles. However if composite dark matter contains stable electrically charged…
Dark Matter (DM) is generally assumed to be massive, cold and collisionless from the structure formation point of view. A more correct statement however is that DM indeed experiences collisional damping, but on a scale which is supposed to…