: : Sorry, I made a mistake in one of my questions, so here they are again: : : : : 1) Do the laws of physics apply at a black hole singularity, or do they break down? Do the fundamental forces of nature reunify at black hole singularities? : : : : 2) What do you suppose happens when a black hole explodes? Might another universe be created? In any case, what would happen to the singularity? : : : : 3) I read somewhere that Stephen Hawking no longer believes that the universe began at the big bang singularity. Instead he seems to think that the universe began as a regular, smooth point of spacetime expanding in an ordered state, becoming increasingly lumpier and disordered with time, and ending in a "big crunch" singularity. Anyone have any details on his theory?Thanks!

: : I like your questions a lot. They are fascinating to think about. Frankly, the laws of physics are what they are; they break down nowhere. Our understanding of them may break down, but the absolute laws of physics will still apply at the singularity. More importantly, whatever the laws are, they will yield consistent results whenever a specified set of conditions are duplicated. For example, a black hole singularity of 20 solar masses will behave like every other black hole singularity of 20 solar masses, all other things being equal. Now the question is, what are the laws of physics?

: : The second question should start with, Does a black hole explode? In theory, perhaps, but we have never seen evidence of this. Apparently, there are ways that black holes can degenerate into radiation products, but I am afraid I am not up on this. How did the Universe begin? perhaps you have seen the theory that the "Big Bang" was actually a big inflation or expansion from a "rupture" of the virtual particle background that underlies space and time; if so, then Hawking may be correct in his new idea. If a black hole explodes, it alone certainly would not have enough mass to start a new universe; but, if it's quantum effects are such that it could rupture the virtual fabric that exists everywhere, then perhaps an nearly endless stream of real quanta could erupt in an inflation from the rupture. Sort of like an exploding bullet starting a hydrogen blimp afire. Hawking's theory sounds good, but it sounds similar to what has gone before; the way is universe is expanding, it much more resembles an inflation than an explosion.

: : I don't have any idea about your most intriguing question, Do all the fundamental forces of the universe become one at the singularity? We already know that the first three (electromagnetism, strong nuclear force and weak nuclear force) are expressions of the same quantum principle; but how does gravity fit in? When gravitation goes to infinity, do the other forces become one with it? What is another way to express this idea? Most fascinating...BJ