THIS ENDS the extraordinary modeling paper on black hole formation in the prestigious journal Nature. It is a difficult and technical paper, but well worth the effort. Black holes are understood almost exclusively by indirect methods and models such as this one. By definition, they cannot be seen, except by their surrounding fiery halo, or the gravitational waves when two merge; but they remain one of the most impressive and enigmatic structures in the universe.
https://www.nature.com/articles/s41586-019-0873-4