Theoretical physicists from Italy, Spain and Argentina propose a new mechanism to create supermassive black holes from dark matter.
Milky Way halos can contain a very dense core of dark matter, which could possibly mimic the effects of a central black hole or eventually collapse to form one. Image Credit: Sci-News.com.
Standard formation models involve normal baronic matter collapsing under gravity to form black holes, which then grow over time.
A research team led by dr. Carlos Argüelles of the Universidad Nacional de La Plata and ICRANet investigated the potential existence of stable galactic nuclei of dark matter and surrounded by a dilute dark matter glory.
They found that the centers of these structures could become so concentrated that they could also collapse into supermassive black holes.
This could happen much faster than other proposed formation mechanisms, and would be able to form supermassive black holes in the early universe in front of the galaxies in which they live, contrary to current understanding.
“This new formation scenario could provide a natural explanation for how supermassive black holes formed in the early Universe, without requiring prior star formation or having to invoke seed black holes with unrealistic growth,” said dr. Argüelles said.
Another interesting consequence of the new model is that the critical mass for collapse in a black hole cannot be reached for smaller dark matter radiations, for example those around some dwarf systems.
The researchers suggest that smaller dwarf galaxies may then be with a central core of dark matter rather than the expected black hole.
Such a dark matter core can still mimic the gravitational signatures of a conventional central black hole, while the outer halo of dark matter can also explain the observed galaxy curves.
“This model shows how dark matter hauls can contain dense concentrations in their centers, which can play an important role in understanding the formation of supermassive black holes,” said Dr. Argüelles said.
“Here we have proved for the first time that such a nuclear halo distribution of dark matter can form in a cosmological framework and remain stable for the life of the universe.”
‘We hope that further studies will shed more light on supermassive formation of black holes in the earliest days of our universe, as well as to investigate whether the centers of inactive galaxies, including our own Milky Way, could host this dense dark . saakkern. ”
The team’s report is in the Monthly notices from the Royal Astronomical Society.
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Carlos R. Argüelles et al. 2021. On the formation and stability of fermionic dark matter hauls in a cosmological framework. MNRAS 502 (3): 4227-4246; doi: 10.1093 / mnras / staa3986
This article is based on text by the Royal Astronomical Society.