Matter creation via vacuum fluctuations in the early Universe and observed ultrahigh energy cosmic ray events
Matter creation via vacuum fluctuations in the early Universe and observed ultrahigh energy cosmic ray events
Cosmic rays of the highest energy, above the Greisen-Zatsepin-Kuzmin cut-off of the spectrum, may originate in decays of superheavy long-living X-particles. These particles may be produced in the early Universe from vacuum fluctuations during or after inflation and may constitute a considerable fraction of Cold Dark Matter. We calculate numerically …