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Sun 27 Jun, 2004 11:09 pm
Could we reason out the theory-- that black holes actually exist everywhere because some black holes exist in outer space or in our universe? If a black hole can swallow down anything, including time and space, our universe now should be just a black hole. But the facts speak louder than eloquence, astronomers just found out there are some black holes in the universe, and we coexist with the seemingly horrified black holes.
"Still," you might reply, "the phenomenon cannot prove your theory that black holes exist everywhere, just somewhere in outer space."
About one year ago, when Prof. Stephen Hawking said that he could make a small man-made black hole in lab and he would win Nobel Prize hence, reporters asked him whether or not the small black hole would swallow down the lab even our planet? The professor replied: Nope, the black hole itself could snap to vanish! He implied this posibilty: black holes might exist everywhere in our universe.
A black hole doesn't have infinite gravity though so something has to come close enough to the black hole to get "pulled" in.
If you could turn the sun into a black hole right now we'd be quite safe except that we'd freeze to death from the lack of heat. We'd still feel the same gravity.
You could compress a pencil into a black hole if you were advanced enough. The pencil blackhole wouldn't "suck" in the Earth.
Gravity is determined by the amount of mass and your distance from its centre of mass.
Well, here's how I think about it.
Could infinite black holes exist in finite space?
Yes. It is possible to have infinite black holes arranged in a fractal array and in such a way that the gravity they each generate cancels each other out to achieve stability.
Could infinite black holes exist in infinite space? Yes..... but much, much, less probable. Fractal theory breaks down when the domain is inifnite and therefore stability is impossible to reach with meager modern physics.
So do black holes exist everywhere in the universe? I don't think that's very likely.
But can there be a patch of space somewhere where there are infinite black holes? Yeah, I'd bet my bottom dollar that there is.
Assuming black holes are absolute then the universe should not exist at all. If the universe started from a tiny point where all the matter in the universe was contained then shouldn't that matter and energy have created a massive black hole rather than a big bang and an ever expanding universe? Unless, as some physicsts postulate, our universe is IN a giant black hole...
The singularity exploded.
NickFun wrote: Unless, as some physicsts postulate, our universe is IN a giant black hole...
It sounds quite funny. If so, that is not a black hole, surely enough.
oristarA wrote:NickFun wrote: Unless, as some physicsts postulate, our universe is IN a giant black hole...
It sounds quite funny. If so, that is not a black hole, surely enough.
Actually, I think this is a serious possibility. Once inside a large event horizon, there would be no way to see out, and the "Universe" would be enclosed, much as ours seems to be.
Infinate is too many for a finite universe but we could have trillions of about Earth mass black holes in our galaxy.
The smallest ones "snap to vanish" according the Steven Hawkings, who would have trouble proving to Nobel orize committe that he made a black hole that promtly vanished. Neil
Hawkings believes that there's 300 small black holes per cubic light year. Small because they were formed by the big bang and don't contain much mass in comparison to a star.
At 300 per cubic light year the closest one on average would be the distance of Pluto away.
We have to remember that much of what we think we know about black holes could be wrong as evidence is scarce and perhaps not what we think.
According to some theories, a million ton black hole would be microscopic, and it's gravity would be close to negligible an inch away. It would however capture a few air molecules in it's acreation disc which would produce gamma rays in dangerous numbers up to perhaps a foot away. It would etch any surface it touched, but would likely not capture mass fast enough to avoid net mass loss due to Hawking radiation, so it would suddenly vanish with a snap. Neil
neil wrote:We have to remember that much of what we think we know about black holes could be wrong as evidence is scarce and perhaps not what we think.
According to some theories, a million ton black hole would be microscopic, and it's gravity would be close to negligible an inch away. It would however capture a few air molecules in it's acreation disc which would produce gamma rays in dangerous numbers up to perhaps a foot away. It would etch any surface it touched, but would likely not capture mass fast enough to avoid net mass loss due to Hawking radiation, so it would suddenly vanish with a snap. Neil
A black hole formed from a massive star is microscopic.
I agree: black holes from massive stars are typically several solar mass, unless perhaps many black holes can occasionally form from one collapsing star.
Some experts suppose that mini black holes = microscopic event horizons formed during the big bang, but they would have evporated long ago unless they were able to injest matter at a high rate. No other ways to create black holes are known, but we don't yet know every thing. The theory is that once created they are valnerable only to evaporation by Hawking's radiation.
It would appear even tiny black holes could gain mass inside a white dwarf or nutron star Neil
neil wrote:I agree: black holes from massive stars are typically several solar mass, unless perhaps many black holes can occasionally form from one collapsing star.
Some experts suppose that mini black holes = microscopic event horizons formed during the big bang, but they would have evporated long ago unless they were able to injest matter at a high rate. No other ways to create black holes are known, but we don't yet know every thing. The theory is that once created they are valnerable only to evaporation by Hawking's radiation.
It would appear even tiny black holes could gain mass inside a white dwarf or nutron star Neil
According to Hawkings the universe's background radiation is still higher than the evaporation rate of the mini black holes and so they wouldn't have evaporated yet.
I believe you need to clarify Hawking's comments - in particular to ask
"theoretically - what is the smallest black hole (event horizon) you could conceivable create and could it be Planck size 10 ^ -42 metres or less?"
If Hawkings where answering that question he was talking about the cosmic foam with the possibility part of what forms spacetime - apart from virtual particles are incredibly tiny black holes that also wink into and out of existence everywhere all the time.
I seem to remember that was part of the context to his statement. The Earth would become a black hole if it where crushed to a diameter of an inch, so maybe Hawkings thought what would happen if an atom or subatomic particle where crushed on that scale too? Could it also become a black hole and if so - if its is so minute could it simply drop out of our existence all together? If its event horizon was trillions of times smaller than the diameter of a quark would it to all intents and purposes simply not be there?
Perhaps that is dark energy - simply super crushed energy carriers that are trillions and trillions of times too small for us to possibly every detect?
/end_spectulation_mode
To put 10 ^ -42 in perspective, a trillion is 10 ^ 12; a trillion cubed is 10 ^ 36, a million times less than 10 ^ 42. Neil
Biggest and oldest black hole to date found
Stanford University :
The black hole, dubbed Q0906+6930, about 10 billion times the mass of the Sun.
English link:
http://www.space.com/scienceastronomy/heavy_blazar_040628.html
Chinese link:
http://tech.sina.com.cn/other/2004-06-30/0752381423.shtml
Hi tobruk: 300 per cubic light year, would be a lattice 1/7 light year = 414 billion miles apart if evenly spaced, which is much farther than to Pluto, but they are moving and not evenly spaced, so closer than Pluto once per century may be correct. Did Stephen Hawkings suggest a mean or average mass (or event horizon radius) for these mini black holes at present?
I think you need to edit or explain "they would not have evaporated yet" Neil
neil wrote:Hi tobruk: 300 per cubic light year, would be a lattice 1/7 light year = 414 billion miles apart if evenly spaced, which is much farther than to Pluto, but they are moving and not evenly spaced, so closer than Pluto once per century may be correct. Did Stephen Hawkings suggest a mean or average mass (or event horizon radius) for these mini black holes at present?
I think you need to edit or explain "they would not have evaporated yet" Neil
They wouldn't have evaporated because to evaporate they would need to be "expelling" more energy than they're taking in. Since the Big Bang's background radiation is higher than the rate they'd be theorised to lose then the black holes wouldn't have been able to vanish yet.
I don't remember what mass he said these black holes created by the big bang would be. Sorry.
rosborne979 wrote:oristarA wrote:NickFun wrote: Unless, as some physicsts postulate, our universe is IN a giant black hole...
It sounds quite funny. If so, that is not a black hole, surely enough.
Actually, I think this is a serious possibility. Once inside a large event horizon, there would be no way to see out, and the "Universe" would be enclosed, much as ours seems to be.
More weird other than interesting. Given the possibility holds, the black hole has formed a huge cave where our universe is living.
It is so hard to imagine. Have you known any link to your hypothesis?
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I do think your hypothesis cannot hold water. Because black hole doesn't swallow down any thing, it still emit radiations about which we can measure, for example X-ray emissions we can measure with the Very Large Baseline Array
Our galaxy has a radius of about 60 thousand light years. Area = 3.14 times 60,000 squared =360 billion square light years. Thickness averages about 10,000 light years 3600 trillion cubic light years. Times 300 = over a million times a trillion mini black holes 10^18. The smallest ones evaporate to a snap in hours, if they can't ingest matter. Since balance is unlikely for 13.7 billion years, most of the smallests mini black holes snapped long ago or grew bigger, so the ones left might average Jupiter mass. A Jupiter mass passing though the inner solar system would change Earth's orbit significantly, even disastrously in a near miss. Neil
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