What collapsed and created the Supermassive black holes in center of galaxies?

"Why are there Black Holes in the Middle of Galaxies?"

www.universetoday.com...

Just a short, interesting article I found when I pondered the same thing a few years ago. In short, astronomers don't know why, but there's one theory that suggests dark matter may have played a part in how they got there.

a reply to: Kromlech
That is interesting article. I wonder if black holes have a surface? All that matter in there condensed into a sphere just inside of the event horizon. I suppose it would be the hardest material that exists? Of course nothing could ever rest on this surface as all things would be crushed and added to it.

I realize space is so very twisted at black holes that people don't imagine one having a surface but surely there is a sphere of something in there in all that twisted space time? Is it just a ball of quarks all smashed together? Energy? Fluid?

a reply to: Xeven

I wonder if black holes have a surface?

A black hole has zero dimensions and therefore no surface.

However, the 'event horizon' -- the point beyond which anything approaching the hole must fall into it -- is normally regarded as its 'surface'. The size of the sphere formed by the event horizon varies with the mass of the black hole. Some black holes have event horizons wider than our Solar System.

It doesn't have the properties of a physical surface, though. It's just an imaginary sphere drawn in space.