Related papers: Antimatter in the Universe
A new concept of generation of the cosmological baryon excess along with the cold dark matter (CDM) in the Universe is proposed and corresponding scenarios are outlined. Possible realizations of the idea in the framework of supersymmetric…
We ask whether the universe can be a patchwork consisting of distinct regions of matter and antimatter. We demonstrate that, after recombination, it is impossible to avoid annihilation near regional boundaries. We study the dynamics of this…
As a result of the Standard Model chiral anomalies, baryon number is violated in the early universe in the presence of a hypermagnetic field with varying helicity. We investigate whether the matter / anti-matter asymmetry of the universe…
A novel mechanism for explaining the matter-antimatter asymmetry of the universe is considered. We assume that the universe starts from completely symmetric state and then, as it cools down, it undergoes a quantum-phase transition which in…
The comparison of cosmic abundances of the light elements with the density of baryonic stars and gas in the universe today provides a critical test of big bang theory and a powerful probe of the nature of dark matter. A new technique allows…
We study a mechanism through which the cosmic dark matter density can be explained simultaneously with the observed baryon asymmetry of the Universe. At the core of our proposal lie the out-of-equilibrium scattering processes of bath…
The existence of antimatter stars in the Galaxy as possible signature for inflationary models with non-homogeneous baryo-synthesis may leave the trace by antimatter cosmic rays as well as by their secondaries (anti-planets and…
Many different mechanisms can contribute to antiprotons and positrons production, ranging from conventional reactions up to exotic processes like neutralino annihilation. The open problems are so fundamental (i.e.: is the universe symmetric…
We will review the main aspects of a mechanism for the contemporary generation of the baryon and Dark Matter abundances from the out-of-equilibrium decay of a Wimp-like mother particle and briefly discuss a concrete realization in a…
We investigate the possibility that dark matter and the baryon asymmetry of the Universe are generated by the same mechanism, following an idea initially proposed by V.A. Kuzmin and recently discussed by R. Kitano and I. Low. In our model,…
In the multiverse, the universes can be created in entangled pairs with spacetimes that are both expanding in terms of the time variables experienced by internal observers in their particle physics experiments. The time variables of the two…
We show that primordial nucleosynthesis in baryon inhomogeneous big-bang models can lead to significant heavy-element production while still satisfying all the light-element abundance constraints including the low lithium abundance observed…
We illustrate, via a simplified model, a scenario in which the baryon-asymmetry and, possibly the dark matter component of the Universe are simultaneously generated by the decay of a WIMP-like mother particle, in turn produced non-thermally…
Additional elementary species and primordial black holes are common candidates for dark matter. Their co-existence in the early Universe leads to accretion if particles are heavy. We solve equation of motion affected by expansion which…
We study the generation of the matter-antimatter asymmetry during bosonic preheating, focusing on the sources of the asymmetry. If the asymmetry appears in the multiplication factor of the resonant particle production, the matter-antimatter…
Recent observations by the Alpha Magnetic Spectrometer (AMS-02) have tentatively detected a handful of cosmic-ray antihelium events. Such events have long been considered as smoking-gun evidence for new physics, because astrophysical…
The apparent dominance of matter over antimatter in our universe is an obvious and puzzling fact which cannot be adequately explained in present physical frameworks that assume matter-antimatter symmetry at the big bang. However, our…
We review the present activities related to hypernuclear production in hadronic in-medium reactions at intermediate energies. The status of theoretical predictions and experimental evidences for the in-medium formation of bound superstrange…
Interactions of heavy Majorana neutrinos in the thermal phase of the early universe may be the origin of the cosmological matter-antimatter asymmetry. This mechanism of baryogenesis implies stringent constraints on light and heavy Majorana…
Various new physics models, e.g., theories of compositeness, can accommodate the color singlet excited leptons that interact with the leptons, quarks, leptoquarks, etc. A particular type of excited lepton, which at low energies interacts…