Abstract

Yet normal particle interactions produce matter and antimatter in equal amounts. If matter and antimatter in the early universe had been in perfect balance, they would long since have been annihilated out of existence, leaving behind a universe of photons and a few electrons. We would not be here to study such a universe, since our very existence depends on the gross excess of matter over antimatter now present. Where did the matter come from? What happened in the early stages of the Big Bang that produced the contemporary dominance of matter?