The resilience of matter's fundamental components

Within a black hole's singularity there is, in theory, zero volume and infinite density. The gravity of something that dense becomes like a particle roach motel. particles check in but they dont check out. Light (photons) do not even exit. Hence the name Black hole.
Black holes do have mass though but they have zero volume at the singularity. Do not worry if that makes no sense to you or if you can not wrap your mind around it. You are in good company.
At a quantum level of such extremes things cease to be things and human understanding of physics breaks down. Energy is the currency of the universe IMO.

an objects mass divided by its volume will give you its density. In the case of a black hole that density will always be an infinite value. Do not think of the Black hole and the singularity as separate. A blackhole terminates at a singularity. (in theory)
Energy is what causes. The causes are what we observe. ***edit to add: I read a cute bumper sticker that said: "Black holes are where God divides by zero."This message has been edited by 1.61803, 05-26-2005 04:21 PMThis message has been edited by 1.61803, 05-26-2005 04:35 PM

A singularity is a point not an object. Sorry but that is just the way it is. But trying to understand how space can be bent to that extreme by infinte density is difficult to conceive. I still have trouble understanding time dilation and quantum entanglement, quantum tunneling. Thinking in terms of size suggest it is an object. That is not the case. Matter itself when you get down to it is just probabilities. So thinking in the quantum world requires you first forget everything you have ever known or thought about the physical intuitive world. I think it was Heisenburg who said:" If you think you understand quantum mechanics then you dont."
***edit to add link, If your interested in the math here http://www.physicsguy.com/ftl/html/FTL_part3.html#eqadef2This message has been edited by 1.61803, 05-27-2005 12:45 PM

I think String theory reach the end of its rope a few years ago.
I read an article, stating that some colleges actually cancelled any course in String from they're curriculum. Remember Greenes book is several years old.