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Here's a better link: Quark mirror
Only $285, huh? I think I'll pass... Back to the actual question, it's unlikely, for when such "mirrors" between us and distant galaxies moved, they'd cause all kinds of funny optic effects that we'd notice, including galaxies and stars moving rapidly or winking in and out of existance, half-galaxies, serious warps, etc. Since we don't see that, we conclude that the fabric of space-time is fairly flat, interrupted only by the occasional star. It's also fairly empty, with about 5 atoms per cubic meter, at least in the observable universe. |
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That wasn't link I found.. mine had real physics in it, but really had nothing to do with my thought.
Thank you mugaliens... but I'm not so sure we would notice it fast enough. If the light coming at us for 20 light years gives us information we believe to be true, and and then moves a little... the only thing we MIGHT notice... is that it is moving in the wrong direction... no? (Like trying to comb the back of your own hair in 2 mirrors and your hand goes the "wrong" way) |
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For distant objects, it's really not feasible to compare photographic plates over 20 years to detect relative motion. For nearby ones, however, it's easy, and the relative motions match predictions for a relatively flat space. We largely extrapolate this for more distant objects and compare what we can, such as red-shifting.
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well... that's pretty much exactly what I'm saying.
At a relatively close distance it is easy and we use that to judge large distances. But could we be fooled if we think we are looking one way when really what we are seeing is somewhere else? Hopefully this isn't ATM.. because it is only a question. I've heard many physicists say that in every direction is the universe... ..and that If I left in a straight line and traveled far enough, I would end up back where I began. Well this question is sort of like that. As if you were inside a gazing ball, and no matter where you looked, anything at the far edge was where you looked from and behind you. Ugh.. it is so hard to put it into a 3D term. Maybe I should just give up before I even start. |
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Einstein played around with some model universes that curved back on themselves. You might be thinking of those. It has been well established for a long time, however, that the "real" universe is flat, i.e. does not curl back on itself.
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PW -- Plant Whisperer |
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I have entertained myself with this question for a while.
Light orbits a black hole at the event horizon. A ray of light can be bent to some degree in other trajectories. So, there could be an intermediate trajectory very close to the event horizon in which light would do a u-turn and head backwards in the direction of the source. It would be a gravitational mirror. In that case, we would be seeing objects where they are not, and even see duplicated objects in different regions of space. We could even see our milky way reflected back. That would have serious implications. That reflected light could be distorted, but the spectral signature would remain the same. I posted something about it a while ago. Gravitational Mirrors
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What brings us together is stronger than what pulls us apart Last edited by Argos; 29-August-2007 at 04:03 PM.. Reason: Grammar |
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Yeah, it would be like taking the spacetime warp to the ultimate consequences. It would be cool if somebody knowledgeable could expand on it.
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What brings us together is stronger than what pulls us apart |
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You might try the WIKI article on manifolds. It's not as daunting as it seems at first. Just read through it, with delving into the math. The concepts of space (and spaces) will be much clearer. |
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So we're not going to see any particularly strange mirroring effects other than from very certain points in space. |
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I have put the picture of the dark matter ring as my computer background an when you discount a few galaxies and a large bright event near the top of the picture it seems that if various spirals were constructed from out to in there appears to be a mirroring effect.
Has there been any talk on that? |
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Yeah, but not all gravitational warpings produce rings or halos. You can also have point sources in deflected trajectories [as in the famous 1919 eclipse].
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What brings us together is stronger than what pulls us apart |
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This was specific to inbound light coming infinately close to the event horizon of a black hole. Obviously at a distance it would merely appear as normal gravitational lensing.
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What's the greatest change in trajectory in degrees of light around a black hole without falling into the event horizon?
Hint, if it spirals in more than 180 degrees, something's wrong. Another hint - light trajectories around black holes remain parabolas (not eclipses). Third hint - where would the apex of the parabola be? Another question: If light is eminating from a distant object towards a black hole, how far around can it go before it impacts the event horizon? |
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What brings us together is stronger than what pulls us apart |
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Unlikely, though, as we can probably discount all such emanating from the viscinity of a black hole. |
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