Over the last few years, as we have been able to peer back deeper and deeper into the early Universe, we have found something very puzzling.
Giant black holes up to a billion times the mass of the Sun formed before the universe was a billion years old. It's difficult to explain the presence and size of black holes given what we know. How did they get there so quickly after the big bang? They got so danged big.
The origin of the stars is explained by the fact that they were formed without the need for exotic conditions. The seeds would have grown into black holes.
Black holes at the center of most massive galaxies can be millions or billions of times the mass of the sun. In 2003 we began to find quasars that were like Cosmic Lighthouses in the early universe.
They didn't understand how they formed. The discovery overturns 20 years of thought on the origin of the first black holes in the universe.
There are two ways in which black holes form. The first model is the bottom one. A star dies and leaves a black hole around 100 times the mass of the sun.
The black hole grows larger and larger until it is millions of times the mass of the Sun. It is very difficult to reconcile with quasars.
If you start with a big black hole, it can be up to 100,000 times the mass of the sun. The stars that collapsed to form these black holes would have only had a short time to live.
We don't know of a current formation mechanism that could produce stars of that mass. Simulations show that stars could have formed at the junctions of rare but powerful streams of dense, turbulent, cold gas in the early universe.
It would need some truly exotic conditions, such as a background of strong ultraviolet radiation or supersonic flows between gas and dark matter, to be possible. The environments in which these early Universe quasars were found were different.
The researchers conducted simulations of the streams of gas and were delighted to find that the black holes formed at the intersection of the streams spontaneously.
Normal stars can't form because of the turbulence generated by intersecting streams. When there's too much turbulence, the conditions aren't stable enough for a dense knot of material in a cold cloud to form a baby star.
The cloud in the simulation grew so large that it collapsed into two huge stars, measuring in at 31,000 and 40,000 times the mass of the sun.
Billions of times the mass of the Sun can form a black hole as gas from the streams feeds into the clouds.
When the first stars in the Universe formed, they created their own massive seeds. The result explains the origin of the first quasars and their numbers at early times.
The first supermassive black holes were the result of structure formation in the dark universe.
The research was published in a journal.
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