The Big Bang time paradox

[Ogie Oglethorpe]

Originally posted by Geronimo


the event horizon does not collapse as the black hole is formed. In fact it expands outwards when ever matter crosses from outside in.

Yep, As long as the hawking radiation for the given black hole is at a lower temp than surrounding universe the black hole will continue to expand as it sucks in more mass than it ejects via hawking radition.

[Kuciwalker]

Originally posted by KrazyHorse
As soon as we understand QFT in curved space I'll tell you.

[Ned]

But, G, isn't the EH a product of gravitational fields? Assuming non uniform fields, the shape of the EH will vary, not so?

But, what happens if gravity in one direction reduces below that necessary to maintian the EH?

[Geronimo]

Originally posted by KrazyHorse


As soon as we understand QFT in curved space I'll tell you.

that won't be difficult at all will it?

[KrazyHorse]

[Geronimo]

Originally posted by Ned
But, G, isn't the EH a product of gravitational fields? Assuming non uniform fields, the shape of the EH will vary, not so?

But, what happens if gravity in one direction reduces below that necessary to maintian the EH?

If you are reducing felt gravity of the singularity by an opposing gravitational tug from another singularity you will never get the EH to move inward such that singularity lies outside the EH.

So long as the EH completely envelopes the singularity distortions in it's shape do not in any way threaten it's integrity.

[Ned]

G, what would happen, in your view, if the gravitational field in a locus reduced below that necessary to maintain the EH?

[Geronimo]

Originally posted by Ned
G, what would happen, in your view, if the gravitational field in a locus reduced below that necessary to maintain the EH?

That would probably depend upon how the gravity were reduced.


But the biggest problem is that the EH won't dissolve in response to changes in the gravitational field. rather it just changes shape. If you directed some sort of hypothetical anti gravity at the region in question you wouldn't reduce gravity below that necessary to maintain the EH unless you somehow directed this anti gravity effect directly at the singularity and it would have to be so strong as to entirely negate the entire gravitational field of the singularity. Every last ounce of it. reduction in the gravity anywhere else it won't matter how strong this (possibly even very exotic) anti gravity phenomena is, there will still be an EH of some size and shape completely enveloping the singularity. likewise directing it at the singularity but not of sufficient effect to totally eliminate the singularitys gravitational field will still leave a region around the singularity where space is so curved that an EH exists.

Of course this is assuming a non rotating black hole.

Rotating black holes with their weird ring singularities will require someone vastly less ignorant than myself to discuss. I personally wonder if a black hole could be spun so fast that it's ring shaped singularity would lie outside of it's event horizon. I'm sure it can't or this would have been a topic of great scrutiny by physicists. maybe the singularity isn't really ring shaped and I'm completely misunderstanding the notion of rotating black holes?

[Ned]

G, isn't an opposite gravitational field (caused by a neaby black hole) equivalent to your anti-gravity field?

[Kuciwalker]

Except the opposed gravitational field is some distance from the other black hole. The resulting gravitational field (and event horizons) would look similar to the electric field of two nearby point charges of the same sign.

[Geronimo]

Originally posted by Kuciwalker
Except the opposed gravitational field is some distance from the other black hole. The resulting gravitational field (and event horizons) would look similar to the electric field of two nearby point charges of the same sign.

thanks

[Geronimo]

can anybody tell me if rotating black holes have ring shaped singularities? wiki wasn't a big help for that question.

[Zkribbler]

I don't think anyone has ever looked inside a black hole to see.

[KrazyHorse]

Also, do not 2) or 3), either alone or together, suggest that dark matter has no charge?

Yes, on the whole. There may be some sort of neutral bound state whose components each have charge, but that hypothesis gets a little complicated.

OMFG. Did I seriously think about this 3 years ago? Three grad students in my department published a paper based on this 2 months ago that's getting rave reviews.

[KrazyHorse]

****ity **** **** ****. ****.