Physicists Propose Exploding Primordial Black Holes Explain Matter-Antimatter Asymmetry

DENVER — A team of physicists has proposed that tiny primordial black holes, formed in the first instants after the Big Bang, could explain the observed dominance of matter over antimatter in the universe. According to the researchers, these black holes would have evaporated and exploded, generating shock waves in the early universe's quark-gluon plasma.

The process, detailed in recent presentations and papers, may have created conditions that led to an excess of matter.

Scientists have long observed that the universe contains far more matter than antimatter, though the early universe is believed to have produced equal amounts of both. Matter and antimatter annihilate upon contact, converting into energy. Without a mechanism to create an imbalance, the universe would consist primarily of energy rather than structures like stars and galaxies.

The proposed primordial black holes would have masses of about 1,000 kilograms, comparable to that of a small car. They formed from density fluctuations in the early universe and existed within the quark-gluon plasma, the high-energy state before protons and neutrons emerged, around a billionth of a second after the Big Bang.

the Shock Waves The explosions would have launched shock waves into the surrounding quark-gluon plasma, injecting energy and creating regions of extreme heat.

Researchers have suggested that the blasts heated small spheres of plasma, potentially forming sharp boundaries with differing conditions inside and outside. This could hypothetically lead to an excess of matter as the shock waves expanded. For the mechanism to account for the universe's matter dominance, numerous such black holes would need to have exploded shortly after the Big Bang.

The proposal provides a potential way to study these elusive black holes, which evaporated too quickly for direct detection.