Related papers: A lower bound on dark matter mass
Building on recently constructed inflationary vector dark matter production mechanisms as well as studies of magnetogenesis, we show that an inflationary dark Schwinger mechanism can generate the observed dark matter relic abundance for…
We present a new mechanism for generating the observed dark matter energy density, through resonant production of vector dark matter during inflation. Resonant amplification of the vector dark matter is achieved through Mathieu…
We investigate a new bound on the low reheating temperature in a scenario where the Universe experiences early matter-domination before reheating after which the standard big bang cosmology begins. In many models of dark matter (DM), the…
We propose a cosmological dark matter production mechanism in the form of a longitudinal massive vector boson. We build upon the work of Graham et.al. including non-minimal couplings of the massive vector with gravity, developing a well…
Ultralight dark matter refers to the lightest potential dark matter candidates. We will focus on the mass range that has been studied using astrophysical and cosmological observations, corresponding to a mass $10^{-24} \, \mathrm{eV}…
We assume that dark matter is comprised of axion-like particles (ALPs) generated by the realignment mechanism in the post-inflationary scenario. This leads to isocurvature fluctuations with an amplitude of order one for scales comparable to…
We use large-scale cosmological observations to place constraints on the dark-matter pressure, sound speed and viscosity, and infer a limit on the mass of warm-dark-matter particles. Measurements of the cosmic microwave background (CMB)…
The small-scale structure problems of the universe can be solved by self-interacting dark matter that becomes strongly interacting at low energies. A particularly predictive model is resonant short-range self-interactions, with a…
We estimate dark matter density for the Universe with a reheating temperature smaller than the mass of dark matter, assuming dark matter to be a weakly interacting massive particle. During the reheating process, an inflaton decays and…
Vector bosons heavier than $10^{-22}$ eV can be viable dark matter candidates with distinctive experimental signatures. Ultralight dark matter generally requires a non-thermal origin to achieve the observed density, while still behaving…
Numerous observations point towards the existence of an unknown elementary particle with no electromagnetic interactions, a large population of which was presumably produced in the early stages of the history of the Universe. This so-called…
Our ignorance of the period between the end of inflation and the beginning of Big Bang Nucleosynthesis limits our understanding of the origins and evolution of dark matter. One possibility is that the Universe's energy density was dominated…
In this exploratory study, we investigate the bounds on the equation of state of dark matter. Modeling dark matter as a fluid component, we take into account both positive and negative fixed equations of state. Using CMB, supernovae Ia and…
Dark matter produced from thermal freeze-out is typically restricted to have masses above roughly 1 MeV. However, if the couplings are small, the freeze-in mechanism allows for production of dark matter down to keV masses. We consider dark…
It is quite plausible that the mass of the dark matter particle increases significantly after its freeze-out, due to a scalar field rolling to large values. We describe a realization of this scenario in the context of thermal inflation…
Kibble mechanism drastically underestimates the production of topological defects, as confirmed recently in atomic and condensed matter systems. If non-thermally produced, they can be cosmological dark matter of mass 1-10 PeV. If…
We show that in large-field inflationary scenarios, superheavy (many orders of magnitude larger than the weak scale) dark matter will be produced in cosmologically interesting quantities if superheavy stable particles exist in the mass…
Motivated by a recent detection of 511 keV photons from the center of our Galaxy, we calculate the spectrum of the soft gamma-ray background of the redshifted 511 keV photons from cosmological halos. Annihilation of dark matter particles…
We study in detail a recently proposed mechanism for producing non-thermal dark photon dark matter at the end of inflation in the mass range $\mu\,{\rm eV} \lesssim m \lesssim 10\,{\rm TeV}$. A tachyonic instability induced by a rolling…
Minimal Supersymmetric Standard Model with gauge mediated supersymmetry breaking has all the necessary ingredients for a successful sub-eV Hubble scale inflation $H_{\rm inf} \sim 10^{-3}-10^{-1}$ eV. The model generates the right amplitude…