Possible origin of antimatter regions in the baryon dominated universe

We discuss the evolution of a $U\left(1\right)\mathrm{}$ symmetric scalar field in the inflation epoch with a pseudo-Nambu-Goldstone tilt being revealed after the end of the exponential expansion of the Universe. The $U\left(1\right)\mathrm{}$ symmetry is supposed to be associated with baryon charge. It is shown that quantum fluctuations lead in a natural way to a baryon dominated universe with antibaryon excess regions. The range of parameters is calculated at which the fraction of universe occupied by antimatter and the size of antimatter regions satisfy the observational constraints, survive to the modern time, and lead to effects that are accessible to an experimental search for antimatter.