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On Friday, April 03, 2015 8:03:12 AM Rich Freeman wrote: |
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> On Fri, Apr 3, 2015 at 7:06 AM, Peter Humphrey <peter@××××××××××××.uk> |
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wrote: |
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> > On Friday 03 April 2015 06:58:38 Rich Freeman wrote: |
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> > |
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> >> I'm not convinced that anybody has proven that quantum behavior is truly |
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> >> non-deterministic |
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> > |
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> > But it must be, surely, since it's probabilistic. I don't see how the |
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domain |
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> > of probabilistic behaviour can overlap the domain of deterministic |
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> > behaviour. |
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> |
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> /me looks over at his handy Plinko board. |
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> |
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> Just because it looks probabilistic, doesn't mean that it is. Take a |
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> cryptographic PRNG. If you know the seed, the output is completely |
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> deterministic. If you don't know the seed, you could describe the |
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> output as probabilistic, and it might look non-deterministic, but it |
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> still is. |
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There's an explanation for uncertainty that makes common sense. Let's say I |
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throw you a ball, you can catch it because you take many measurements of it's |
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location and your brain tries to predict it's path. But this only works |
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because the ball is so massive and the photons that we use to see it are |
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massless so the effect of them colliding with the ball is neglible. Imagine if |
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the only way you could "see" the ball was by throwing another ball at it and |
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seeing where it landed, it would then be nearly impossible to predict it's |
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path because everytime you measure it you'll get it of course, so the |
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principle of uncertainty would hold even though the ball was really on a well |
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defined path. See |
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http://en.wikipedia.org/wiki/Uncertainty_principle#Heisenberg.27s_microscope |
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Some claims still boggle my mind (superposition in macroscopic objects), like |
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the "tunning fork" (probably a quartz crystal) experiment on this page: |
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http://en.wikipedia.org/wiki/Quantum_superposition#Experiments_and_applications |
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But that's just one sentence stating that the tuning fork can be in a |
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superposition of the vibrating and non-vibrating state but I'm sure if you find |
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more info about the experiment is not as fantastic as it sounds. |
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If we ever figure this to be wrong it'll probably just obsolete quantum physics |
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so instead of deterministic quantum computing we'll have something else. |
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> The biggest problem I have with quantum mechanics is that there is no |
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> understanding of underlying mechanisms. We have models that describe |
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> experiments, which is great, but not really a satisfying solution. I |
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That's the problem with science in general. The one thing it may never be able |
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to answer is "why?". Take gravity as an example. We got really good models for |
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it, we can predict how it influences even light with great accuracy but what |
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are the underlying mechanisms? We may never know. Einstein would say it's |
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because matter bends space, but what is the underlying mechanism for that? We |
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just take his word for it because he gave us equations that work better than |
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anything else we've come up with so far. |
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-- |
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Fernando Rodriguez |
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