Does God exist?

[Ben Kenobi]

Naked singularities are weird as all hell. I hope one of our astronomy majors or physics majors shows up to help discuss this because I wouldn't mind some clarification about how the lack of an event horizon (ie it's 'nakedness') can allow a singularity to behave so weirdly but you can find plenty of allusions to this fact by googling naked singularity.

Well, I'll confirm that they can behave strangely, but I've never heard such thoughts applied to the singularity at the big crunch.

I didn't get that far into quantum mechanics when I was an astronomy major, but we'll have to wait for Krazyhorse.

[Ned]

Two questions:

1) What happens when two black hole meet?

2) Can a singularity explode by turning a great deal of its mass into energy like ordinary fusion reactions?

[Ramo]

1. Assuming you mean the singularities meet, their masses, angular momenta, and charges combine, and become a bigger singularity.
2. Current physics cannot model what happens at a singularity.

Regarding naked singularities, IIRC it has to do with the singularity having a large angular momentum relative to its mass (in the Kerr geometry), or a high electric charge relative to its mass (in the Reissner-Nodstrom geometry) .

[Geronimo]

Originally posted by Ramo
1. Assuming you mean the singularities meet, their masses, angular momenta, and charges combine, and become a bigger singularity.
2. Current physics cannot model what happens at a singularity.

Regarding naked singularities, IIRC it has to do with the singularity having a large angular momentum relative to its mass (in the Kerr geometry), or a high electric charge relative to its mass (in the Reissner-Nodstrom geometry) .

i've heard of those two possible special cases of a possible naked singularity but I don't think either is related to the singularity at the big bang.

[Ned]

Again I am still not getting a simple answer here. Can a singularity explode and create a universe?

[Geronimo]

Originally posted by Ned
Again I am still not getting a simple answer here. Can a singularity explode and create a universe?

Some singularities can some can't and it depends on the environment of the sigularity I guess. I still think one of the critical distinctions between the two is that only a naked singularity can 'explode'. A singularity under an event horizon is not free to behave in any way that would violate its event horizon. It is proving tough to find a nice credible link that discusses this though.

[Ramo]

i've heard of those two possible special cases of a possible naked singularity but I don't think either is related to the singularity at the big bang.

Was pointing out what I really knew about it (quantitatively). You might be able to get it without a relatively large angular momentum or charge with some fancy metrics.

Again I am still not getting a simple answer here. Can a singularity explode and create a universe?

Probably, but we have absolutely no idea why or how it happens.

[Ned]

Then, if a singularity can explode, then I would suggest that is more probable that this universe itself originated from just such an explosion.

[Geronimo]

Originally posted by Ned
Then, if a singularity can explode, then I would suggest that is more probable that this universe itself originated from just such an explosion.

more probable than what? The current big bang model requires that the universe originate from a singularity 'explosion'.

[Ned]

Geronimo, but others have said that prior to the big bang there was nothing but energy.

[Ned]

Further, Ben, I believe, said that an infinite cycle between big bang, expansion, contraction, crunch to a singualarity and then another big bang, was impossible. Which is it?

[Geronimo]

Originally posted by Ned
Geronimo, but others have said that prior to the big bang there was nothing but energy.

Probably a misunderstanding stemming from semantics. Ordinarily 'prior to the big bang' would be considered meaningless because time is impossible without space and at the start of the big bang, the big bang singularity contained all of the space in a single point (ie there was no space so there was no time either). Possibly people meant that there was only energy in the universe until long enough after the start of the big bang for matter to begin to condense.

[Geronimo]

Originally posted by Ned
Further, Ben, I believe, said that an infinite cycle between big bang, expansion, contraction, crunch to a singualarity and then another big bang, was impossible. Which is it?

Depends on how he meant impossible. He might have meant that based upon our best current observations of the universe it would be impossible for the expansion to slow and reverse meaning that a big crunch would be unable to occur.

[alva]

Everything you always wanted to know about God & does he really exist