10-19-2010, 04:45 AM | #76 | |
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10-19-2010, 06:30 AM | #77 | |
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10-19-2010, 08:21 AM | #78 | |
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With all due respect, I don't have a theory. I merely note that the mathematics of Maxwell's equations boundary conditions allow the possibility of C not being invariant. I also note that historically, the close correlation between Maxwell's boundary condition calculation of C and the measured value of C was considered a fact in favor of relativity (prior to the 1919 eclipse experiment). I fully note that the natural universal background (permeability and permittivity) are constant. I merely note that since 1999, we have figured out a way to alter the permeability and permittivity artificially. Can this have an effect on C? The mathematics imply it. Should they not be tested? No matter what the experiment revealed, the result would be interesting. If I had a few million on the side, I'd fund the experiment. as it is, I merely note it. You know, from 1800 to 1895, everybody was certain light was a wave. It has been experimentally proven, again and again... |
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10-20-2010, 05:53 AM | #79 | |
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Intuitively and without having a look at the math involved, I'd guess that, since no information is permitted to escape the black hole, the entanglement would break the moment one of the particle passes across the event horizon. |
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10-20-2010, 06:14 AM | #80 | |
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Not that I know much about it - so I may be talking rubbish. |
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10-20-2010, 06:45 AM | #81 | |
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Also, it's important to note that the act of measuring a quantum system doesn't change it's energy. |
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10-20-2010, 06:57 AM | #82 |
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That's really not changed, though. Quantum mechanics describes a photon as an "energy function", but it can still perfectly satisfactorily be described as a wave, when you want to talk about its wave-like properties.
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10-20-2010, 06:58 AM | #83 | |
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"When particles decay into other particles, these decays must obey the various conservation laws. As a result, pairs of particles can be generated that are required to be in certain quantum states." If the entanglement breaks when one particle traverses an event horizon - wouldn't that mean one particle can be resolved while the other isn't? |
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10-20-2010, 07:09 AM | #84 | |
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Edit to answer the second question as well: I'm actually not too sure about what would happen to the particles if the entanglement breaks. I think that, on one hand, the conservation laws still apply, but then you couldn't break the entanglement without collapsing both wavefunctions. If we apply this to the case of pushing one particle over the event horizon of a black hole, that would, I believe, constitute an information transfer, which is prohibited. The caveat is that I didn't think about what constitutes information, which is a little more complicated in these cases and is, I suspect, extremely relevant in this case. Last edited by Manichean; 10-20-2010 at 07:15 AM. |
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10-20-2010, 02:20 PM | #85 | |
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You are talking about Bell's Inequality. A superficial reading of the situation would fool one into thinking this could be used to transmit information faster than light, or from inside a black hole's event horizon to the exterior. Sorry, that turns out not to be the case. Say you have a source of quantum entangled particles. One particle goes off to your friend at Alpha Centauri. You measure the polarization of the particles pair you have, which instantly changes the polarization of the particle pair at Alpha Centauri. FTL communication, right? Nope. What you get at your end is a stream of random numbers. No information there. Your friend at Alpha Centauri has a stream of random numbers. No information there. However, if your friend sends you his stream of random numbers (either at the speed of light via radio, or slower than light by traveling by rocket), then you can compare the two sets of random numbers. Which will tell you that, yes, sometime in the past, FTL information was transmitted. But the only way to get the information out of this is to compare the two lists, and the only way to compare the lists is to re-send the information slower or at the speed of light. Which sort of defeats the purpose of FTL. It is even worse with the black hole situation, since it is impossible to transmit the second list out of the event horizon by slower or at the speed of light rates. So no, you cannot use Bell's Inequality to send information out of an event horizon. |
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10-20-2010, 06:26 PM | #86 | |
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Smolin presents the rise and fall of string theory as a morality play. He accurately captures the excitement that theorists felt at the discovery of this unexpected and powerful new idea. But this story, however grippingly told, is more a work of drama than of history. Even the turning point, the first crack in the facade, is based on a myth: Smolin claims that string theorists had predicted that the energy of the vacuum—something often called dark energy—could not be positive and that the surprising 1998 discovery of the accelerating expansion of the universe (which implies the existence of positive dark energy) caused a hasty retreat. There was, in fact, no such prediction. Although his book is for the most part thoroughly referenced, Smolin cites no source on this point. He quotes Edward Witten, but Witten made his comments in a very different context—and three years after the discovery of accelerating expansion. Indeed, the quotation is doubly taken out of context, because at the same meeting at which Witten spoke, his former student Eva Silverstein gave a solution to the problem about which he was so pessimistic. This episode also goes to show that, contrary to another myth, young string theorists are not so intimidated by their elders. As Smolin charts the fall of string theory, he presents further misconceptions. For example... To read the full review, go to http://www.americanscientist.org/boo...all-strung-out. |
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10-20-2010, 06:50 PM | #87 | |
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10-20-2010, 06:58 PM | #88 | |
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10-20-2010, 07:01 PM | #89 | |
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10-20-2010, 07:06 PM | #90 | |
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