Related papers: Cosmic Birefringence Triggered by Dark Matter Domi…
We offer a new solution to an old puzzle in the penguin-dominated $B\to\pi K$ decays. The puzzle is the inconsistency among the measurements of the branching ratios and CP asymmetries of the four $B\to\pi K$ decays: $B^+ \to \pi^+ K^0$,…
We search for dark matter in the form of axionlike particles (ALPs) in the mass range $5.576741 \,\mathrm{neV/c^2}$ - $5.577733\,\mathrm{neV/c^2}$ by probing their possible coupling to fermion spins through the ALP field gradient. This is…
For the minimal QCD axion model it is generally believed that overproduction of dark matter constrains the axion mass to be above a certain threshold, or at least that the initial misalignment angle must be tuned if the mass is below that…
The string/$M$ theory Axiverse -- a plethora of very light Axion Like Particles (ALPs) with a vast range of masses -- is arguably a generic prediction of string/$M$ theory. String/$M$ theory also tends to predict that the early Universe is…
Axion rotations can simultaneously explain the dark matter abundance and the baryon asymmetry of the Universe by kinetic misalignment and axiogenesis. We consider a scenario in which the Peccei-Quinn symmetry breaking field is as large as…
A model is presented where there exists another U(1) gauge group which is extremely weakly coupled to that of QED except inside the core of domain walls. It is possible to choose parameters such that standard model photons crossing such a…
Making robust predictions for the phase space distribution of dark matter at the solar neighbourhood is vital for dark matter direct detection experiments. To date, almost all such predictions have been based on simulations that model the…
The cosmic birefringence (CB) angle refers to the rotation of the linear polarization plane of Cosmic Microwave Background (CMB) radiations when parity-violating theories are considered. We analyzed the Quantum Boltzmann equation for an…
Predicting the local flux of dark matter particles is vital for dark matter direct detection experiments. To date, such predictions have been based on simulations that model the dark matter alone. Here we include the influence of the…
We propose new signals for the direct detection of ultralight dark matter such as the axion. Axion or axion like particle (ALP) dark matter may be thought of as a background, classical field. We consider couplings for this field which give…
We investigate scenarios in which dark matter is stabilized by an abelian Z_N discrete gauge symmetry. Models are surveyed according to symmetries and matter content. Multi-component dark matter arises when N is not prime and Z_N contains…
We study the experimental constraints on a model of a two-component dark matter, consisting of the QCD axion, and a scalar particle, both contributing to the dark matter relic abundance of the Universe. The global Peccei-Quinn symmetry of…
Progress in observational cosmology over the past five years has established that the Universe is dominated dynamically by dark matter and dark energy. Both these new and apparently independent forms of matter-energy have properties that…
The similar cosmological abundances observed for visible and dark matter suggest a common origin for both. By viewing the dark matter density as a dark-sector asymmetry, mirroring the situation in the visible sector, we show that the…
We study axion dark matter production from a misalignment mechanism in scenarios featuring a general nonstandard cosmology. Before the onset of Big Bang nucleosynthesis, the energy density of the universe is dominated by a particle field…
We consider cosmological consequences of the spontaneous breaking of a global symmetry that is anomalous under technicolor interactions, leading to the emergence of a light axion-like particle. Avoiding overclosure of the universe by such…
Cosmic acceleration is widely believed to require either a source of negative pressure (i.e., dark energy), or a modification of gravity, which necessarily implies new degrees of freedom beyond those of Einstein gravity. In this paper we…
We propose a new alternative to the Weakly Interacting Massive Particle (WIMP) paradigm for dark matter. Rather than being determined by thermal freeze-out, the dark matter abundance in this scenario is set by dark matter decay, which is…
An axion cloud surrounding a supermassive black hole can be naturally produced through the superradiance process. Its existence can be examined by the axion induced birefringence effect. It predicts an oscillation of the electric vector…
The densities of dark and baryonic matter are comparable: \zeta = \rho_D / \rho_B ~ O(1). This is surprising because they are controlled by different combinations of low-energy physics parameters. Here we consider the probability…