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Loading contentThe unexplained fact that the Universe is made almost entirely of matter, even though the Big Bang should have produced matter and antimatter in equal amounts, which would have annihilated completely. Why a tiny excess of matter survived — the problem of baryogenesis — is one of the great open questions in physics and cosmology.
Facts on this topic will be cited from these primary and reference sources.
Mission data, planetary science, space telescopes, and public-domain imagery.
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