What’s more, the new study hints at the existence of a multiverse, in which our universe is just one of many in a broader and more complex structure. If there is an “outside” to our universe, then an external observer might see the entirety of everything we know—stars, galaxies, and billions of light years of space—as a puny primordial black hole.
“We still don’t know what dark matter is made of, but, since the black holes are known to exist, it is natural to ask whether dark matter could be composed of black holes that could form before the stars and galaxies formed,” said Alexander Kusenko, an astrophysicist at UCLA who led the new study, in an email.