I think Steve was correct in what he said:
"We can all agree that the more massive a black hole is the smaller the circumference of the black hole's event horizon will be. Therefore, can a black hole ever have enough mass to where its event horizon closes in on itself? If so, what would happen?
I think that if all of time/space, mass and energy coalesced in a singularity, there would have to be a type of explosion where the inverse would be everything will be expanding.".
It seeems to me, the event horizon of a black hole is the horizon, viewed from inside the black hole, where the escape velocity of a light beam is greater than the speed of light, and thus is the horizon where all lght escaping from the hole would be bent back into the hole. The more massive the black hole, the smaller (in radius inside the black hole) that event horizon would be. A supermassive black hole, say containing ten thousand stellar masses, would have a vastly smaller event horizon **inside the black hole** than a black hole containing say one stellar mass at its core; but the actual supermassive black hole itself would be the same size as any other black hole.
The Schwarzschild radius concerns masses and observers and phenomena outside of a black hole, not mass within a black hole, it relates how much mass is required to generate a black hole. Once the black hole forms, though, it can suck in mass from beyond its event horizon, which will cause the event horizon to decrease in diameter inside the black hole (IOW a light beam or an atomic particle generated inside the black hole will be turned back into the hole, unable to escape, at distances much closer to the the singularity at the center of the black hole because the gravitational force acting on that light beam, attributable to the gravity of that mass inside the black hole, will be stronger in proportion the mass within that singularity at the center.
http://en.wikipedia.org/wiki/Event_horizon
"In general relativity, an event horizon is a boundary in spacetime, most often an area surrounding a black hole, beyond which events cannot affect an outside observer. Light emitted from beyond the horizon can never reach the observer, and any object that approaches the horizon from the observer's side appears to slow down and never quite pass through the horizon, with its image becoming more and more redshifted as time elapses. The traveling object, however, experiences no strange effects and does, in fact, pass through the horizon in a finite amount of proper time."
...
"...The most commonly known example of an event horizon is defined around general relativity's description of a black hole, a celestial object so dense that no matter or radiation can escape its gravitational field. This is sometimes described as the boundary within which the black hole's escape velocity is greater than the speed of light. A more accurate description is that within this horizon, all lightlike paths (paths that light could take), and hence all paths in the forward light cones of particles within the horizon, are warped so as to fall farther into the hole. Once a particle is inside the horizon, moving into the hole is as inevitable as moving forward in time (and can actually be thought of as equivalent to doing so, depending on the spacetime coordinate system used). ..."
Pete B
