Super-massive black holes have been found to rotate at near light speed. They are just "sloppy eaters" and what is not immediately sucked in when their gravity crushes something before swallowing it is spun outwards and away from them. It was shown recently that a particular black hole had a safe orbit a mere 100 miles away from it, despite being a number of solar masses. This shows that material need not get too far from any black hole to be safe. Billions of years of this "dust formation" (especially the very early period) could account for some dark (unseen) matter.
Klippymitch. If you have a titanic explosion in space, then matter will rush away from a central point. Unless gravity can pull it back, it will "go on forever". Space (near us) is maybe ten atoms per cm3. Maybe one atom per cm3 in intergalactic space. Even if you got it down to zero, it isn't going to pull matter back. That only works in an atmosphere where air rushes in to fill a vacuum, taking material with it.
Too simple for you? Yeah I know... it was a lot funner to say a black hole was a magical hole in space that just sucked things into it.
