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ArcticMyst Security by Avery

Is the universe infinite or finite?

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Exactly what I asked... Where does this mass / energy go? I don't think we have detected it yet.

HMike

like i said the radiation is shot out of the black hole(usually out of the axis on both sides i think) into space thats where all the mass and energy goes, into space. thats why they think the miniature black holes in the particle collider will disapear it only has to get rid of a couple protons mass in radiation, whereas actual black holes have to get rid of whole stars which takes a very long time.

and like mrgreenjeans said theyre trying to prove it with the particle collider. IMO i think that theory is right but well see
 
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like i said the radiation is shot out of the black hole(usually out of the axis on both sides i think) into space thats where all the mass and energy goes, into space. thats why they think the miniature black holes in the particle collider will disapear it only has to get rid of a couple protons mass in radiation, whereas actual black holes have to get rid of whole stars which takes a very long time.
Yes, you're basically right about this, the phenomenon is called, as others have pointed out, "Hawking Radiation" as it was originally predicted by Stephen Hawking back in the 70s. It basically describes how a black hole "disintegrates" over time, as its mass gradually is gradually re-emitted as thermal radiation by the black hole. Where does the energy go? The best anyone can tell is that it radiates outward just like a star radiates light radially outward into free space. (It's interesting to note that the smaller the black hole, the faster the rate at which it disintegrates; the reason for which this happens is not entirely understood, as Hawking Radiation has yet to be physically observed. And as kevin pointed out, while it is possible for high energy particle colliders like the LHC to produce tiny black holes, they would certainly disintegrate before it has a chance to grow at all; again the reason for this is two-fold, it has an exponentially higher rate of radiation than cosmic-scale black holes, AND there is a LOT less mass to convert into radiation.)

Where does the expanded universe expand into? No one really has any idea and I'm not sure that we will ever know to sure. Personally I don't think humans have the ability to comprehend anything it WOULD expand into, since it's can't be three dimensional space, but something entirely different. It's the same problem we hit when we wonder "What happened before the big bang?" We might be able to theorize about it, but any current or foreseeable technology wouldn't allow us to actually SEE beyond our own existence.

As far as the universe being infinite or finite...I think Daguin makes a excellent point when he said that words are meaningless constructs humans love assigning to things and phenomenon :p... That being said, if you subscribe to any of the "Multiverse" theories, such as the many worlds interpretation of quantum mechanics, there would be an infinite number of "realities". Each of these are only separated by a single quantum discrepancy, encompassing every possible quantum state. (Of course it's fun to think that, if this interpretation is true, there is a universe out there with literally any set of conditions you could imagine! Sometimes I'd like it to be true just for that aspect :D )

Is our own "bubble" universe infinite? Well...I suppose at any given instance it has a finite dimension...but since it's constantly in a state of accelerated expansion, then it would be expanding into infinity. Another thing to consider is, like the many worlds theory, it's always been theorized that our own "bubble" is MUCH larger than we think, so much so that conditions begin to repeat themselves, leading to potentially more instances of our own world, or ones incredibly similar to it, all within our same universe! But the likelihood of us coming in contact with these worlds so similar to our own (or any intelligent life IMHO) is impossibly slim.
 
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zaery

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The visible universe is literally expanding at the speed of light. That is because the light from the part that we can't see yet hasn't reached us. Depending on your interpretation of that, you could say that:
1) It's infinite because what we see is growing at a constant speed and doesn't show any signs of stopping.
2) It's a finite size, growing at the speed of light, and there's no way to prove that wrong, because to prove that wrong, you would need some sort of energy to reach us, and if that energy(light) reaches us, then it's defined as part of the finite universe.

Either way, the visible universe is finite.
 

mfo

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The visible universe is literally expanding at the speed of light. That is because the light from the part that we can't see yet hasn't reached us. Depending on your interpretation of that, you could say that:
1) It's infinite because what we see is growing at a constant speed and doesn't show any signs of stopping.
2) It's a finite size, growing at the speed of light, and there's no way to prove that wrong, because to prove that wrong, you would need some sort of energy to reach us, and if that energy(light) reaches us, then it's defined as part of the finite universe.

Either way, the visible universe is finite.

Actually, the expansion of the universe is accelerating.
 
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I have trouble understanding relativity. So if I throw a rock at 99% of c, then the rock I threw, threw another rock at 99% of c and so on and so forth, why wouldn't it eventually catch up with the edge of space time? From my perspective none of those rocks would be traveling at faster than the speed of light right? but from the perspective of each individual rock they would still be able to throw a rock at 99% of c right?

If of course rocks could throw rocks.
 
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i dont know about rocks :p but i THINK scientists have proven that even if you are traveling half the speed of light, and you shine a laser in the direction you are traveling it will still only move at c. crazy how that stuff works
 
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move at c relative to me at my moving speed? or move at c relative to my starting point from where i began accelerating up to 50% of c?

I know time has some role because there is no center point of the universe where relative to that point nothing can travel faster than c. im thinkin it is gonna need too much splainin for a forum topic
 
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no i believe its like this: some how a space ship moves at 50% of c. it carries a man with a laser. there is also another man with a laser floating still in space. as the space ship passes the man they both point their lasers at a common target at the instant they are equidistant from the target they both turn on their lasers and the light gets there at the same time... dont quote me on that though the thread rule says i cant research it haha
 
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ya but then that means that the guy on the space ship witnesses light traveling at 50% of c (which i think is impossible unless you make an adjustment in time). from the space ships POV his light should hit the target first, but from the standing still guys POV they would both hit target at the same time.

edit: wait that doesn't work nm. im lost
 
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no i believe its like this: some how a space ship moves at 50% of c. it carries a man with a laser. there is also another man with a laser floating still in space. as the space ship passes the man they both point their lasers at a common target at the instant they are equidistant from the target they both turn on their lasers and the light gets there at the same time... dont quote me on that though the thread rule says i cant research it haha
This is fact, the phenomenon is generally explained by Einstein's theory of special relativity. The speed of light in a vacuum NEVER changes, so when you fire it from the space ship, the very fabric of space-time warps to compensate. Light is just that cool ;)
 
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ok so its not impossible to see two things moving away from eachother at faster than c, just impossible to move faster than c.
 
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\
ya but then that means that the guy on the space ship witnesses light traveling at 50% of c (which i think is impossible unless you make an adjustment in time).[/QUOTE]

thats what the theory of time travel is based on. if you went around the "target" and came back (it took you 10 minutes) then the guy sitting still would have aged aprox. 15 minutes. btw that estimate is in no way mathmatically correct. i dont think its that easy
 
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I have trouble understanding relativity. So if I throw a rock at 99% of c, then the rock I threw, threw another rock at 99% of c and so on and so forth, why wouldn't it eventually catch up with the edge of space time? From my perspective none of those rocks would be traveling at faster than the speed of light right? but from the perspective of each individual rock they would still be able to throw a rock at 99% of c right?

If of course rocks could throw rocks.

Important, rock have mass. If a rock traveling a 99% of C threw another rock in the same direction of travel that rock would only gain a little increase in speed. Most of the energy imparted into the throw would increase the second rocks mass.

Spacetime is a description that tells where and when of some object . It has no edge.
 
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no i believe its like this: some how a space ship moves at 50% of c. it carries a man with a laser. there is also another man with a laser floating still in space. as the space ship passes the man they both point their lasers at a common target at the instant they are equidistant from the target they both turn on their lasers and the light gets there at the same time... dont quote me on that though the thread rule says i cant research it haha

I believe that's not true, but a don't remember well enough to explain why it's not it at this time.
 




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