Antimatter as a probe for physical processes in the early Universe

Alexander Sakharov; Maxim Khlopov; Sergei Rubin

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Antimatter as a probe for physical processes in the early Universe

Alexander Sakharov·Maxim Khlopov·Sergei Rubin

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Abstract

The whole set of astrophysical data indicates that our Universe is globally baryon asymmetrical. Nevertheless a possibility of existence of relatively small amount of sufficiently large antimatter regions is not excluded. Such regions can survive the annihilation with surrounding matter only in the case if their sizes exceed a certain scale. It is shown that quantum fluctuations of a complex scalar field caused by inflation can generate large antimatter domains progenitors, which contribute insignificantly to the total volume of the Universe. The resulting distribution and evolution of such antimatter regions could cause every galaxy to be a harbour of an anti--star globular cluster. The existence of one of such anti -- star globular cluster in our Galaxy, does not contradict the observed $γ$ -- ray background, but the expected fluxes of $\bar{^4He}$ and $\bar{^3He}$ from such an antimatter object can be searched for in PAMELA experiment and are definitely accessible for the sensitivity of coming AMS02 experiment.

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Alexander Sakharov, Maxim Khlopov, Sergei Rubin. 2001-11-28. Antimatter as a probe for physical processes in the early Universe. https://arxiv.org/abs/astro-ph/0111524

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