Related papers: Dark matter in $R+R^2$ cosmology
What is the upper limit of the mass of the neutralino dark matter whose thermal relic is consistent with the observation? If the neutralino dark matter and colored sparticles are extremely degenerated in mass, with a mass difference less…
Stable particle dark matter may well originate during the decay of long-lived relic particles, as recently extensively examined in the cases of the axino, gravitino, and higher-dimensional Kaluza-Klein (KK) graviton. It is shown that in…
We explore the cosmology of the Dark Dimension scenario taking into account perturbations in the linear regime. In the context of the Dark Dimension scenario, a natural candidate for dark matter in our universe is the excitations of a tower…
The gravitino may well play an important role in cosmology, not only because its interactions are Planck-suppressed and therefore long-lived, but also because it is copiously produced via various processes such as particle scatterings in…
It has been suggested that Einstein's theory of General Relativity can be modified to accomodate mismatches between the gravitational field and luminous matter on a wide range of scales. Covariant theories of modified gravity generically…
The case grows ever stronger that the average density of matter, ordinary and dark, is less than the critical density required for a flat universe. However, most of determinations of the mass density have been dynamical, hence sensitive…
The distinction between modified gravity and quintessence or dynamical dark energy is difficult. Many models of modified gravity are equivalent to models of coupled quintessence by virtue of variable transformations. This makes an…
This work investigates the dark matters structures that form on the smallest cosmological scales. We find that the types and abundances of structures which form at approximately Earth-mass scales are very sensitive to the nature of dark…
The nature of Dark Matter remains one of the outstanding questions of modern astrophysics. The success of the Cold Dark Matter cosmological model argues strongly in favor of a major component of the dark matter being in the form of…
Recently, the static spherically symmetric solution of the gravitational field equations have been found in theories describing massive graviton with spontaneous breaking of the Lorentz invariance. These solutions, which show off two…
The cosmological observations coupled with theoretical calculations suggest the existence of enormous amount of unseen and unknown matter or dark matter in the universe. The evidence of their existence, the possible candidates and their…
Observations provide increasingly strong evidence that the universe is accelerating. This revolutionary advance in cosmological observations confronts theoretical cosmology with a tremendous challenge, which it has so far failed to meet.…
Primordial black holes that survive until the present have been considered as a dark matter candidate. In this paper we argue that primordial 2-2-hole remnants provide a more promising and testable option. 2-2-holes arise in quadratic…
In R parity conserving supersymmetric theories the lightest superpartner (LSP) is stable. The LSPs may comprise a large fraction of the energy density of the current universe, which would lead to dramatic astrophysical consequences. In this…
We consider a simple class of models in which the dark matter, X, is coupled to a new gauge boson, phi, with a relatively low mass (m_phi \sim 100 MeV-3 GeV). Neither the dark matter nor the new gauge boson have tree-level couplings to the…
Exotic dark matter together with dark energy or cosmological constant seem to dominate in the Universe. An even higher density of such matter seems to be gravitationally trapped in our Galaxy. The nature of dark matter can be unveiled only,…
Dark matter substructure has the potential to discriminate between broad classes of dark matter models. With this in mind, we construct novel solutions to the equations of motion governing condensate dark matter candidates, namely axion…
The introduction of electroweak multiplets that transform under any representation of the standard $SU(2)_L$ gauge group suggests the existence of electrically neutral stable particles capable of serving as cold dark matter in the…
The nature of the cosmological dark matter remains elusive. Recent studies have advocated the possibility that dark matter could be composed of ultra-light, self-interacting bosons, forming a Bose-Einstein condensate in the very early…
Dark matter (DM) could be a relic of freeze-in through a light mediator, where the DM is produced by extremely feeble, IR-dominated processes in the thermal Standard Model plasma. In the simplest viable models with the DM mass below the MeV…