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Old 03-20-2012, 11:09 AM
 
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Quote:
Originally Posted by Brian.Pearson View Post
It could happen to one of us, maybe?
Help me out here. What could maybe happen to one of us?
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Old 03-20-2012, 03:49 PM
 
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Quote:
Originally Posted by NightBazaar View Post
We can't say Gravity has no influence at the subatomic or quantum scales though. Possible examples: micro black holes, quantum gravity.
Thanks NB ... as i hadn't pondered about gravity and quantum black holes before your posting about it .
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Old 03-20-2012, 04:00 PM
 
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I am wondering if dark energy could be involved in the evaporation of black holes, particularly
micro black holes. My thinking is that possibly because they only last for a tiny instant before they evaporate, possibly dark energy overcomes the small amount of gravity holding them together. Just speculating out loud, of course. Does anyone have any thoughts on this?
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Old 03-20-2012, 04:40 PM
 
Location: Texas
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Quote:
Originally Posted by NightBazaar View Post
Help me out here. What could maybe happen to one of us?
It was just a tongue in cheek suggestion that such a thing "could happen."
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Old 03-20-2012, 06:30 PM
 
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Quote:
Originally Posted by Brian.Pearson View Post
It was just a tongue in cheek suggestion that such a thing "could happen."
LOL! Agreed!
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Old 03-21-2012, 03:06 PM
 
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Quote:
Originally Posted by orogenicman View Post
I am wondering if dark energy could be involved in the evaporation of black holes, particularly
micro black holes. My thinking is that possibly because they only last for a tiny instant before they evaporate, possibly dark energy overcomes the small amount of gravity holding them together. Just speculating out loud, of course. Does anyone have any thoughts on this?
That's a stumper. There's a lot of unknowns involved and a lot of ideas tossed out as possible explanations, especially with regard to Dark Energy.

I would think that Dark Energy could be involved with everything, particularly if is responsible for the expansion of space, which seems more apparent at very large scales. Where it seems less apparent is a more localized scales where matter is more densely clustered together and gravity still maintains a hold.

I'm not really certain as to whether micro black holes are the same as the large black holes populated around the universe. The reason I say that is because stellar mass black holes are generated by the gravitational collapse (an implosion) of a star. Super massive black holes might originate in a similar fashion. Micro black holes might be found in nature around the universe, but they're too small to observe. However, it may be possible to observe effects resulting from high energy collisions (an explosion) of particles. So far, none have been observed. As far as I know, the only reason a micro black hole has such a short life is because they are too small to absorb matter to last longer, so they evaporate out of existance.

So we have to different things that seem to work in different ways. Gravity is an attractive force that is stronger between two objects of mass or energy. The greater the distance, the weaker the gravitational attraction. On the other hand, Dark Energy may get its strength by creating more space. The more space it creates, the stronger it gets. But it's strength is related to the expansion of space. That said, the distance between the nucleus of an atom and the electron shell is proportionally huge. There's a lot of space in between. In a nutshell, there's far more empty space than there is matter. The volume of space between the nucleus and the electons is also proportionally smaller than the overall volume of space in the entire universe. In other words, although Dark Matter may very well be at work in the space between the nucleus and the electons, gravity as well as electromagnetism, still hold more of a grip to keep these particles together. Dark Energy may be at work, even at such small scales, but since the scales are so small and because other forces are at work, any effects of the expansion of space at such small scales would be difficult to determine and would not be as proportional as the entire space of the universe. It gets down to relativity.

The evaporation of micro black holes may not have much of anything to do with Dark Matter overcoming the small amount of gravity, but is simply because micro black holes are too small to absorb any matter in order to last any longer.

Below are some links that don't exactly answer your question directly (partly because there's a lot that's still unknown) but are really interesting, especially in terms of the subject of Dark Energy. I had no idea there were so different views, but I'm not really surprised by it either.

Anyway, that's my 2-cents on the subject. By no means can I be sure it's the only answer though. But I'm in good company because no one else knows for sure either.


Micro Black Holes
PhysOrg Mobile: What are 'mini' black holes?

The case for mini black holes - CERN Courier


Dark Energy
Dark Energy, Dark Matter - NASA Science

What Is Dark Energy? | Space.com

Dark energy - Wikipedia, the free encyclopedia
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Old 03-21-2012, 06:08 PM
 
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But isn't it true that atoms in black holes are highly compressed with repect to one another? If so, couldn't it be possible that the evaporation of microblack holes is merely the result of dark energy decompressing these highly compressed atoms, that at some point, perhaps when the the size of the Schwarzschild radius, which is directly proportional to the amount of mass that is squeezed, changes, the matter undergoes a sort of phase change, and evaporation begins? Even though the change in the space between individual atoms is relatively small, taken as a whole, could it be ehough it induce evaporation? Note, I'm just speculating here so maybe it just doesn't work like this. I'm a geologist, not a particle physicis and know very little about, for instance, Hawking radiation.

Last edited by orogenicman; 03-21-2012 at 06:16 PM..
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Old 03-21-2012, 10:47 PM
 
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Quote:
Originally Posted by orogenicman View Post
But isn't it true that atoms in black holes are highly compressed with repect to one another? If so, couldn't it be possible that the evaporation of microblack holes is merely the result of dark energy decompressing these highly compressed atoms, that at some point, perhaps when the the size of the Schwarzschild radius, which is directly proportional to the amount of mass that is squeezed, changes, the matter undergoes a sort of phase change, and evaporation begins? Even though the change in the space between individual atoms is relatively small, taken as a whole, could it be ehough it induce evaporation? Note, I'm just speculating here so maybe it just doesn't work like this. I'm a geologist, not a particle physicis and know very little about, for instance, Hawking radiation.
We don't really know what goes on deep inside a black hole, do we? Atoms would become greatly compressed, so much that they too are crushed apart as they get closer to the singularity, perhaps breaking down to quarks. Gravity is attractive, in effect, compressive. Dark Energy on the other hand appears repulsive, at least with regard to space, meaning it makes space stretch or become larger.

Interestingly, that light can be trapped by a black hole it's easy to think that it must be faster than light. It isn't though. It's no faster or slower than light. It's just stronger.

Since a lot isn't known about Dark Energy, as I think I mentioned, it could be some kind of force or property of space-tme itself. It's thought that the more it expands space, the stronger it gets. However, it seems like its effects are more noticable at very large scales. At smaller scales, like the solar system, the galaxy, galaxy clusters, it doesn't seem as noticable on objects because of gravity which involves objects of matter and energy. Gravity holds things together, but it doesn't compress space.

Concerning micro black holes, the problem is that they're probably not any larger than an atom. My understanding is that they would generally slide by an atom. The main thing is they aren't large enough to exist long. I would presume the Hawking Radiation (black body radiation) is emitted from the micro black hole following the collision of the destroyed particles, usually protons. On the other hand, since micro black holes are so small, if they appear in space, then quantum mechanics would likely be involved.

With regard to evaporation, when particles escape from a black hole, the black hole loses a small amount of its energy, and therefore loses some of its mass. With a micro black hole, since there just isn't much to begin with, it sure couldn't emit much radiation, which in effect means an incredibly short life becaue it would blow it all away almost immediately. In any case, these things are so small than none of it would be directly visible. Instead, with high energy particle accelerators like the LHC, they'd be detected by the effects, presumably from particle tracks forced to curve along with the micro black hole's spin, like an accretion disk. That would suggest that a micro black hole, or at least some of them, have a spin. I think one of the previous links shows a thumbnail illustration like that. Just click the pic to enlarge it.

There's a brief description by the University of Oregon that explains the Hawking Radiation in a way that's pretty easy to understand. Color illustrations too (for simple-minded folks like me to better visualize)! Hey, I'm no expert either, but such subjects really interesting to learn about. Anyway, scroll down to the bottom of the page. There are some other interesting things on that page as well.
unification, spacetime foam, quantum vacuum, quantum fluctuations



Hawking radiation - YouTube
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Old 03-21-2012, 11:46 PM
 
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Thanks, NightBazaar.
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Old 03-24-2012, 09:27 PM
 
Location: Texas
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"These hugely massive black holes were already full--grown when the universe was very young, less than a tenth of its present age."

Suppose the earlier black holes were so big that they would never dissipate?
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