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Astronomy

Primordial Black Holes as Dark Matter Candidates

Quick fact

If all dark matter were made of primordial black holes, then every cubic light-year of space would contain a black hole about the mass of a small asteroid (roughly 10^18 kg). Such light PBHs would be hard to detect because their gravitational lensing effects are tiny and they would have just survived evaporation by now.

Why this is interesting

Dark matter makes up about 85% of all matter in the universe, yet we have never seen it directly. What if some of that dark matter is made of black holes that formed in the very first moments after the Big Bang?

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Primordial Black Holes as Dark Matter Candidates

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