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Post by Progenitor A on Feb 14, 2011 19:44:56 GMT 1
Look at this picture When a photon is emitted from the source It meets a half-silvered mirror. Splitting into two wave functions (IT PROBABLY DOES!), one is reflected vertically, the other goes straight through The vertically-travelling photon-wave-function meets a fully silvered mirror and is reflected to the right. The photon-wave function that is travelling horizontally after meeting the first half-silvered mirror now meets its own full-silvered mirror and is reflected vertically. There are 2 photon-detectors at point A and Point B.that detect the arrival of the 2 (probably split) photon wave-functions Would you expect a 50% probability of either detector A or detector B registering the arrival of a photon? Well, Penrose says no There is 100% probability of detector B registering the arrival of a photon, 0% probability of detector A OK, so what? But If Path A or Path B is BLOCKED, then it is equally probable that the photon will arrive at A or B. Somehow the photons KNOW that there are two routes or 1 route and adjust themselves accordingly! Hmmmm... The photon will only arrive at A if one route is blocked Puzzling? I'll say so, what? How on earth does the photon know that one route is blocked? Now the really puzzling thing is that if the path length is one light year, the photon still knows whether the other route is open or blocked! AGAIN, ACTION AT A DISTANCE SPOOKY HUH?
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Post by abacus9900 on Feb 14, 2011 20:29:37 GMT 1
naymissus, fact is they do not know. They make up nice stories and use gobbledygook to sound like they do know but they do not, and people like STA swallow it all like the good disciple she is!
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Post by abacus9900 on Feb 14, 2011 20:31:11 GMT 1
naymissus, fact is they do not know. They make up nice stories and use gobbledygook to sound like they do know but they do not, and people like STA swallow it all like the good disciples they are!
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Post by speakertoanimals on Feb 14, 2011 20:38:31 GMT 1
What is missing from this is that you have to set up the Mach-Zehnder interferometer such that destructive interference means that you get probability zero at one detector, and probability one at the other.
The real sexy bit is making a bomb detector! We suppose we have a bomb with a very sensitive trigger (a mirror), and we use that as one of the reflecting mirrors in one of the arms.
If the bomb is a dud, it just acts like a mirror, and detector A never clicks. BUT if it is a live bomb, then there is a prob of 1/2 it explodes.
But if it doesn't explode, we now know that photon didn't go that way, in effect. Hence the photon went the other way, and now 50% chance that it will be detected at A, and 50% at B. Multiply that by 50% chance bomb doesn't explode, and we get:
1/2 the time bomb explodes
1/4 time bomb doesn't explode, and we detect photon at B. Doesn't tell us about bomb, could have been a dud.
BUT the remaining quarter of the time, we detect the photon at A, AND the bomb doesn't explode -- but we know it is NOT a dud!
SO how does that pesky photon know about the innards of the bomb device!
Actually, it is just a version of the double-slit experiment, where the double slits are replaced by the two arms of the interferometer, and the bomb is replaced by a detector at one slit. Which as in the double slit case, destroys the interference pattern. Hence if we sometimes detect photons at places where we would expect zeros in the interference pattern, we know a photon detector was at one slit, even though it didn't go off.
Just to be pedantic, the single photon wave-function is non-zero along both arms, there aren't two wave functions!
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Post by abacus9900 on Feb 14, 2011 21:09:12 GMT 1
The delayed choice quantum eraser experiment is even weirder and quite clearly demonstrates that human consciousness is what makes reality.
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Post by speakertoanimals on Feb 14, 2011 21:41:47 GMT 1
No it doesn't -- stop coming out with the same ole quantum woo-woo bollocks!
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Post by abacus9900 on Feb 14, 2011 22:19:48 GMT 1
No it doesn't -- stop coming out with the same ole quantum woo-woo bollocks! Oh come on Speaker, you know it's impossible to interpret it any other way and I notice, BTW, that you haven't even attempted to! Hmmm..... STA, you must never be afraid to say 'I can't explain it', we're not gods you know.
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Post by Progenitor A on Feb 15, 2011 8:30:55 GMT 1
Tut tut, Abacus! Why do you persist so? Is it simply English good manners? Ill-advised old chap! (As you well know)
Now of course, they (scientists or anyone else)do not know. Penrose himself (in the same article) freely discusses the contradictions and unsatisfactory philosophical nature of the conclusions drawn from such experiments. Feynman states quite clearly and unambiguously that we do not undestand what is going on In fact only a fool would claim to know exactly what is going on in these experiments
But are they not fascinating!
In the OP experiment if one route is closed after the launch of the photon then ther is certainty that the photon will choose the open route!
It does not matter where the route is closed either.
For example if the routes are 10 light years long, then the photon 'knows' that one route is closed and chooses the other route years before the other route is blocked !
Remarkable, quite remarkable.
We are indeed at the very limit of knowledge, not really understanding what knwledge is
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Post by abacus9900 on Feb 15, 2011 11:12:26 GMT 1
The universe is basically non-local naymissus and this kind of experiments confirms it! We know that quantum objects are 'spread out' and only take on a particle-like characteristic when we examine them. Don't forget that the universe was once a 'singularity' so it looks as though it still is in some sense and is still 'one.' Conclusion: we are all connected and this is not just 'woo-woo' but scientifically correct! Where do you think telepathy comes from? The spacetime model of the universe popularized by Einstein and others is only a surface feature of realty but there is a more fundamental structure to it and I think the kind of phenomena you have introduced here gives us clues about it. Light itself might just be an 'echo' from more deeper levels of reality and this is not just my opinion. Michio Kaku thinks this might be true too and he's a clever bloke!
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Post by Progenitor A on Feb 15, 2011 12:58:09 GMT 1
Michio Kaku eh?
Never heard of him!
Must look him up
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Post by abacus9900 on Feb 15, 2011 13:32:54 GMT 1
Michio Kaku eh? Never heard of him! Must look him up mkaku.org/
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Post by Progenitor A on Feb 15, 2011 13:56:19 GMT 1
Ah! now I recognise him!
He was one of the physicists on a Horizon programme that we discussed recently
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Post by speakertoanimals on Feb 15, 2011 15:09:37 GMT 1
More out-right insights (Whoops, don't know how that got there, should have, of course, been more out-right LIES, which is what I thought I typed. Must have pressed paste by mistake.........) Go read any article on interpretations of quantum theory. You'll find that the consciousness causes collapse line is a minority view: en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics
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Post by speakertoanimals on Feb 15, 2011 15:11:03 GMT 1
Rather a shame really -- rather than discussing this intriguing experiment, we instead just go back to the same quantum woo-woo nonsense that we ended up with on every other thread that attempted to discuss quantum theory.
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Post by abacus9900 on Feb 15, 2011 15:30:06 GMT 1
Ah! now I recognise him! He was one of the physicists on a Horizon programme that we discussed recently Yes, and STA thinks he's wrong! What does that tell you? I mean, millions have heard of him but only a few people have heard of STA.
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