Astronomers have a new theory about the formation of supermassive black holes.
Extremely bright objects that first appeared close to the birth of the universe — theoretical objects called “dark stars” — could have seeded supermassive black holes over millions of years, according to a new Astronomy story about University of Michigan physicist Katherine Freese.
Dark stars wouldn’t have been much like the stars we’re used to: rather than balancing out gravitational forces with heat dissipated by nuclear fusion reactions, dark stars would have been far less dense, mostly made up of hydrogen and helium. That means they could have swelled up to outrageous sizes compared to today’s stars.
The energy that stopped them from collapsing in on themselves is thought to have come from dark matter particles — which have still never been observed directly — that annihilate each other, releasing energy in the process.
“They can keep growing as long as there is dark matter fuel,” Freese told Astronomy. “We’ve assumed they can get up to 10 million times the mass of the Sun and 10 billion times as bright as the Sun, but we don’t really know. There is no cutoff in principle.”To read more, click here.