Primordial antimatter in the contemporary universe

Abstract

In some baryogenesis scenarios, the universe acquires a non-vanishing average baryonic charge, but the baryon to photon ratio is not spatially constant and can be even negative in some space regions. This allows for existence of lumps of antimatter in our neighborhood and the possibility that very compact antimatter objects make a part of cosmological dark matter. Here I discuss the peculiar signatures which may be observed in a near future.