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Big deal. There's nothing shocking or spooky about two billiard balls being made to spin in arbitrarily opposing directions, selecting only one (omg! without di

Big deal. There's nothing shocking or spooky about two billiard balls being made to spin in arbitrarily opposing directions, selecting only one (omg! without discovering which way it spins, you guys), then separating them, and then noticing the spin of one, in order to reliably grasp that the other is the reversal. I have two guitars. I place the guitars facing one another, such that plucking the HIGH E string on one, also plucks the LOW E string on the other. We put ear plugs in our ears, such that I can separate the two guitars, without us ever hearing them. I pluck the guitars, give you one, and take the other one and travel far away. I then listen to my guitar. It is the HIGH E guitar. Now I know you have the LOW E guitar. Wow. Incredibly unspooky. Not teleportration.

ChrisClark 8y ago
https://en.wikipedia.org/wiki/Local_hidden_variable_theory https://en.wikipedia.org/wiki/Local_hidden_variable_theory https://en.wikipedia.org/wiki/Bell_test_experiments#Hensen_et_al.,_Giustina_et_al.,_Shalm_et_al._(2015):_%22loophole-free%22_Bell_tests https://en.wikipedia.org/wiki/Bell_test_experiments#Hensen_e...
- crumpington 8y ago
  These links are intended to suggest something contrary to what I've said, but they do not suggest any contradiction.
  - bazinga56 8y ago
    Im not an expert so from my outside viewpoint I think by taking the guitar far away you are implying possibility of faster than light communication, which is thought to be not possible, so his links address that? Hard for me to understand so I'm just saying my thoughts out loud to get clarified, thanks
    - crumpington 8y ago
      The quantum state of interest is induced when plucking the conjoined "guitars". (analog for particles) That state is induced at the moment the guitars share "locality" because entanglement requires locality for initialization of polarization. So then, we say we are as yet unaware of the qualities of the polarization we, ourselves, induced. Very mysterious. So spooky, yes? We do not measure, because we choose not to, so we do not yet know. Even if we prevent ourselves from having the capacity to measure, the results hold true, but so what? And so what, if we ask others to do the same. Imagine that we ask two waiters to tape two coins together in the kitchen, flip the linked coins, peel the coins apart while preserving the outcome of the coin flip, then take one coin to your table, and one to mine. Now I know which side of the coin you are looking at, without walking over to your table. So what. Nothing about this claims transmit information superluminously. In reality, with instrumentation, carrier signals relay an electromagnetic transmission in such a way that one cannot peek or tamper (the waiters can't change the coin flip, we cannot hear the ringing guitar), but this does not invalidate the premise of the analog. For the purposes of the analogous guitar example, we say that our couriers (electromagnetism itself) are prevented from touching or listening to the ringing guitars, or disclosing what they might sense. With the guitars, we say the guitars move away from the place where they were entangled. We'll say that our instrumentation rang the guitars at the grand canyon. Our couriers then transported the guitars to you, at the top of the Empire State Building in New York, and me on the Golden Gate Bridge in San Francisco. I receive the guitar, and discover that the LOW E string is ringing, it can only mean that you guitar's HIGH E string in ringing in New York. There are no local hidden variables in this example. The premise of polarity as a corollary for guitar strings is modeled in the exact same manner. Six strings on a guitar maps to the same essential parameters of each of two directions for all three axes of spin.
      - deleted 8y ago
        [deleted]
      - danbruc 8y ago
        You are missing the point of Bell test experiments. Such experiments demonstrate that which guitar is the high E one and which is the low E one is not decided when they are still together. It is not that you and everyone else just don't know which way it is until someone listens to one of them, it is actually not yet decided until someone listens to one of them.
mundo 8y ago
> There's nothing shocking or spooky about two billiard balls being made to spin in arbitrarily opposing directions, selecting only one, then separating them, and then noticing the spin of one, in order to reliably grasp that the other is the reversal. Okay. So now, make two billiard balls so that they're spinning opposite directions, and separate them to opposite sides of the table. Then, go to ball A and do something to it that reverses its spin. Then observe the spins of the two balls. Are they the same? For billiard balls, yes. If ball A is spinning clockwise and ball B is spinning counter-clockwise, and you reverse the spin of ball A, then you will observe both balls to be spinning counter-clockwise. For quantum particles, no. If we manufacture two entangled electrons such that observing them will reveal them to have opposite spin, you can reverse the spin of one of them, and then observe them, and they will both still have opposite spin.
- zackmorris 8y ago
  Unfortunately I don't think this is true. The moment you observe them, they are no longer entangled. So they have opposite spin at that point, but if you reverse one, it behaves classically and both electrons then have the same spin. I'm still trying to wrap my head around why there isn't some hidden variable though which determines which spin they'll have. Like with Bayes' theorum, I keep learning it but for whatever reason my brain won't remember it and I have to look it up again hahah.
  - mundo 8y ago
    Correct, this only works if you can reverse the particle's spin without observing it. This is a descriptive example - the real experiment is slightly more complicated - but it was experimentally verified by Alain Aspect in 1982. If you want a more detailed explanation I recommend http://scienceblogs.com/principles/2007/02/22/spooky-action-at-a-distance-1/ http://scienceblogs.com/principles/2007/02/22/spooky-action-...

ChrisClark 8y ago

https://en.wikipedia.org/wiki/Local_hidden_variable_theory https://en.wikipedia.org/wiki/Local_hidden_variable_theory https://en.wikipedia.org/wiki/Bell_test_experiments#Hensen_et_al.,_Giustina_et_al.,_Shalm_et_al._(2015):_%22loophole-free%22_Bell_tests https://en.wikipedia.org/wiki/Bell_test_experiments#Hensen_e...

crumpington 8y ago
These links are intended to suggest something contrary to what I've said, but they do not suggest any contradiction.
- bazinga56 8y ago
  Im not an expert so from my outside viewpoint I think by taking the guitar far away you are implying possibility of faster than light communication, which is thought to be not possible, so his links address that? Hard for me to understand so I'm just saying my thoughts out loud to get clarified, thanks
  - crumpington 8y ago
    The quantum state of interest is induced when plucking the conjoined "guitars". (analog for particles) That state is induced at the moment the guitars share "locality" because entanglement requires locality for initialization of polarization. So then, we say we are as yet unaware of the qualities of the polarization we, ourselves, induced. Very mysterious. So spooky, yes? We do not measure, because we choose not to, so we do not yet know. Even if we prevent ourselves from having the capacity to measure, the results hold true, but so what? And so what, if we ask others to do the same. Imagine that we ask two waiters to tape two coins together in the kitchen, flip the linked coins, peel the coins apart while preserving the outcome of the coin flip, then take one coin to your table, and one to mine. Now I know which side of the coin you are looking at, without walking over to your table. So what. Nothing about this claims transmit information superluminously. In reality, with instrumentation, carrier signals relay an electromagnetic transmission in such a way that one cannot peek or tamper (the waiters can't change the coin flip, we cannot hear the ringing guitar), but this does not invalidate the premise of the analog. For the purposes of the analogous guitar example, we say that our couriers (electromagnetism itself) are prevented from touching or listening to the ringing guitars, or disclosing what they might sense. With the guitars, we say the guitars move away from the place where they were entangled. We'll say that our instrumentation rang the guitars at the grand canyon. Our couriers then transported the guitars to you, at the top of the Empire State Building in New York, and me on the Golden Gate Bridge in San Francisco. I receive the guitar, and discover that the LOW E string is ringing, it can only mean that you guitar's HIGH E string in ringing in New York. There are no local hidden variables in this example. The premise of polarity as a corollary for guitar strings is modeled in the exact same manner. Six strings on a guitar maps to the same essential parameters of each of two directions for all three axes of spin.
    - deleted 8y ago
      [deleted]
    - danbruc 8y ago
      You are missing the point of Bell test experiments. Such experiments demonstrate that which guitar is the high E one and which is the low E one is not decided when they are still together. It is not that you and everyone else just don't know which way it is until someone listens to one of them, it is actually not yet decided until someone listens to one of them.

mundo 8y ago

> There's nothing shocking or spooky about two billiard balls being made to spin in arbitrarily opposing directions, selecting only one, then separating them, and then noticing the spin of one, in order to reliably grasp that the other is the reversal. Okay. So now, make two billiard balls so that they're spinning opposite directions, and separate them to opposite sides of the table. Then, go to ball A and do something to it that reverses its spin. Then observe the spins of the two balls. Are they the same? For billiard balls, yes. If ball A is spinning clockwise and ball B is spinning counter-clockwise, and you reverse the spin of ball A, then you will observe both balls to be spinning counter-clockwise. For quantum particles, no. If we manufacture two entangled electrons such that observing them will reveal them to have opposite spin, you can reverse the spin of one of them, and then observe them, and they will both still have opposite spin.

zackmorris 8y ago
Unfortunately I don't think this is true. The moment you observe them, they are no longer entangled. So they have opposite spin at that point, but if you reverse one, it behaves classically and both electrons then have the same spin. I'm still trying to wrap my head around why there isn't some hidden variable though which determines which spin they'll have. Like with Bayes' theorum, I keep learning it but for whatever reason my brain won't remember it and I have to look it up again hahah.
- mundo 8y ago
  Correct, this only works if you can reverse the particle's spin without observing it. This is a descriptive example - the real experiment is slightly more complicated - but it was experimentally verified by Alain Aspect in 1982. If you want a more detailed explanation I recommend http://scienceblogs.com/principles/2007/02/22/spooky-action-at-a-distance-1/ http://scienceblogs.com/principles/2007/02/22/spooky-action-...