Ancient fat black holes created by belching Big Bang's dark matter

Streams of gas slammed into cloud of baffling cosmic material – new theory

The largest and oldest supermassive black holes were created from a giant clump of dark matter and gas after the Big Bang, according to a supercomputer simulation.

Supermassive black holes have long been a mystery to the world's eggheads. It’s a puzzle how the gigantic voids over 13 billion light years away – and date back to when the universe was less than a billion years old – grew up to billions of times the mass of the Sun in such a short time.

Previous theories have suggested that they were formed after the first generation of stars fizzled out, or after a huge primordial gas cloud collapsed directly into a black hole. Those theories aren't perfect, though.

A paper published on Thursday in Science describes another method for creating the mega space voids. By assuming more realistic settings and modeling the way gas and dark matter interact with each other, boffins now believe that a massive cloud of dark matter formed when the universe was just 100 million years old.

Passing streams of supersonic gas were caught by the dark matter cloud to generate a dense, turbulent cluster, where a protostar began to take shape. As more gas was trapped, the star swelled to a massive size without releasing radiation.

Naoki Yoshida, co-author of the paper and a researcher at the Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Japan, said that once the star reached a whopping 34,000 times the size of our Sun, it collapsed to leave a massive black hole.

These massive black holes, born from giant ancient stars, continued to grow, and merged together to become supermassive black holes.

Shingo Hirano, co-author of the study and an astrophysicist at the University of Austin, Texas, said the simulations showed that “the number density of massive black holes is derived to be approximately one per a volume of three billion light-years on a side – remarkably close to the observed number density of supermassive black holes.”

The research team, based in America, Japan and Germany, used Aterui, a supercomputer at the National Astronomical Observatory of Japan, to carry out their simulations. ®