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Icenova
2008-Mar-27, 05:59 PM
There is a lot of great astrophysics now available for casual readers and viewers like me, and it is fun to speculate and cross reference ideas. The episode of the Universe (History Channel) on black holes describes that at some point matter that gets too close is stretched, rotated, and heated into a plasma around the black hole. This process is speculated to also occur inside the event horizon around the singularity.

Could tidal forces and the warped space around the singularity form a system where radiation dissapates outward, not escaping from inside the event horizon, but escaping away from the singularity as matter is stretched inward? As matter approaches the singularity it loses all its motional energy and the singularity itself becomes a Bose–Einstein condensate. From watching the Nova (PBS) episode on Bose–Einstein condensate, matter in such a state loses its particle nature and behaves as overlapping waves. Perhaps the singularity is not a point of collapsed particles, but a point of overlapping waves of matter. As waves, would the singularity better achieve super compression?

If particles can be compressed experimental in a Bose-Einstein condensate using laboratory methods, and if the results of such a compression where high enough, then maybe it could give insight into the formation of the singularity and quantum gravity.

John Mendenhall
2008-Mar-27, 07:18 PM
As matter approaches the singularity it loses all its motional energy and the singularity itself becomes a Bose–Einstein condensate.



Interesting idea. Do you have a reference?

Thanks, John M.

Icenova
2008-Mar-27, 10:02 PM
No references. I thought about how a magnetic bowl was used to cool the atoms to form a Bose–Einstein condensate in a laboratory. As atoms fall toward the singularity they are pulled apart by tidal forces, so the energy that holds the particles of the atom together is released. The released radiation is then trapped by the treadmill effect or caught in orbits around the singualrity while the matter spirals further downward. If the process is thorough enough (or even possible), then the particles could lose all motional energy before reaching the singularity.

darkdrag0nlq
2008-Mar-28, 02:36 AM
Wouldn't losing all motional energy just be reaching absolute zero, which is impossible anyways? There always has to be some motion, even if it's really small.

Cougar
2008-Mar-28, 03:18 AM
The episode of the Universe (History Channel) on black holes describes that at some point matter that gets too close is stretched, rotated, and heated into a plasma around the black hole.
Sounds about right. Also, if the hole is spinning, it seems that not only the matter but also the adjacent spacetime itself starts to get dragged around in the process.


This process is speculated to also occur inside the event horizon around the singularity.
I haven't heard too much speculation about what's going on in there. Of course, different size holes can have greatly different effects as one crosses the event horizon.


Could tidal forces and the warped space around the singularity form a system where radiation dissapates outward, not escaping from inside the event horizon, but escaping away from the singularity as matter is stretched inward?
My unprofessional guess would be no. A beam of light at the event horizon in a (hypothetical) circular orbit around the center of the hole could not escape, so it could not get any further away from the hole's center, whatever that is.

All that infalling mass/energy has to do something. It's all still there and gravitationally affects its surroundings, just like before. We just don't have the physics that explains what ultimately stops the gravitational compression and where and at what density. I venture to think that most scientists agree that "infinite density" makes no sense.

Cougar
2008-Mar-28, 03:23 AM
Oh, and welcome to the board, Icenova.



"If history has taught us one thing it is that, with hindsight, newly discovered laws always turn out to be quite logical extensions of what we have already known for a long time." -- Gerard 't Hooft

darkdrag0nlq
2008-Mar-28, 03:30 AM
I think the whole "infinite density" thing is just a sloppy way of saying "we don't know how much, but it's alot."

alainprice
2008-Mar-28, 03:37 AM
My unprofessional guess would be no. A beam of light at the event horizon in a (hypothetical) circular orbit around the center of the hole could not escape, so it could not get any further away from the hole's center, whatever that is.

All that infalling mass/energy has to do something. It's all still there and gravitationally affects its surroundings, just like before. We just don't have the physics that explains what ultimately stops the gravitational compression and where and at what density. I venture to think that most scientists agree that "infinite density" makes no sense.

Light speed orbit around a black hole is at twice the event horizon, or radius. Once you touch the event horizon, it's game over.

neilzero
2008-Mar-28, 10:31 AM
Light speed orbit likely is not at twice the event horizon radius for any size black hole, but there will be a circular orbit at 0.999c at some multiple of the event horizon radius; perhaps 1/5 the radius for a typical super massive blackhole.
What goes on inside the event horizon of any size blackhole is as speculative as most of the topics in ATM = against the mainstream. That will likely remain true even if a black hole passes within 10,000 kilometers of Earth.
For super massive black holes, it seems to me, the event horizon is a sizable volume from which multistage rockets could escape, if their fuel has sufficient energy density and they have sufficient reaction mass.
If we assume the singularity has a radius in the Planck length to pico meter range, then the average density of the singularity is one google = 10E100 times the density of water. Stuff spiraling into that surface is traveling almost c and suffering colissions, so it is very hot = trillion degrees c in my opinion. The temperature at the exact center seems irrelevent. We could argue that there are no molecules intact, so there is no molecular vibration and thus it is cold, but that seems bad logic to me. Neil

trinitree88
2008-Mar-28, 06:37 PM
All right...(no offense, Grey)...we have black holes, and white holes postulated, is there anything about grey holes somewhere?...a combination of the two? pete

never mind, should have just Googled it,....see:http://adsabs.harvard.edu/abs/1989Ap&SS.159..301T

alainprice
2008-Mar-28, 08:48 PM
Light speed orbit likely is not at twice the event horizon radius for any size black hole, but there will be a circular orbit at 0.999c at some multiple of the event horizon radius; perhaps 1/5 the radius for a typical super massive blackhole.


What?

If a photon is orbiting a massive, object, it will move at c. I am considering these orbits only, not the orbit of a particle with mass. Why do you believe light speed orbit to not likely be anything specific? This guesswork is just that, guesswork.

neilzero
2008-Mar-29, 02:06 AM
Hi alainprice: In a vacuum photons travel at c, weather orbiting or not. Typically near the event horizon the vacuum is imperfect so the photons travel a bit less than c, perhaps much less than c if the gravity is one trillion g. Neil