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There is absolutely no way to understand quantum mechanics without learning the math. All metaphors are faulty and will lead you to incorrect conclusions. Fortu

There is absolutely no way to understand quantum mechanics without learning the math. All metaphors are faulty and will lead you to incorrect conclusions. Fortunately the advent of quantum computing has made the math quite easy - it's just linear algebra of the type one would pick up within the first week of an undergraduate course. I made a video aimed at computer scientists which you might find useful: https://www.youtube.com/watch?v=F_Riqjdh2oM https://www.youtube.com/watch?v=F_Riqjdh2oM

qbutt 5y ago
This talk is excellent. Thank you for that. I think an issue with communicating the lack of information transmission is that the statement usually fails to acknowledge two aspects: 1) We are unable to reliably force any one entangled particle to a specified state prior to measurement. ( You mention this more passively in a gp >"First of all, we don't know which color is in which envelope at the start." ) 2) After measuring we have now entangled our particle to our measurement. So, if after our measurement we change the state of our particle the previously entangled particle fails to reliably correlate. Information is transmitted; it's useful information that we are unable to communicate. If I give you instructions saying if the envelope contains this then do this or if it contains that then do that, you can use the information from the particle's entanglement to make that decision, but because of 2) you can only use it to make that decision reliably once, and because of 1) those two outcomes will have to be equally desirable for this form of communication; making it useless. Just roll a dice.
- zelphirkalt 5y ago
  Couldn't one argue, that in some situations coordination via previously agreed upon criteria is worth more than which one of two decisions is made? If A and B agree upon, that B will know what A is doing in either case of discovery, then B needs only to look at their observation and will know what A's observation is (the opposite). Then B can know how A will act, because A decides what to do based on what they observe. Then B can act in a coordinated way. Even though it is only a roll of a die, it can still be helpful. For Sci-Fi example: Some alien spaceship fleet (bare with me!) wants to attack another civilization from 2 sides across wast distances. They split up waaay before that and each keeps an entangled particle. They agree upon which observation means what detail in the first fleet's attack plan. Depending on that, the second fleet will act differently on the other side. But the first fleet only decide which of the 2 strategies to use, when they are already split up, based on the observation of the entangled particle. The second fleet has to act accordingly, or the strategy will fail. Is this impossible? Or is this simply not seen as useful information in some specific definition?
  - ahelwer 5y ago
    You can accomplish the same thing with a PRNG initialized to the same seed.
  - qbutt 5y ago
    > Or is this simply not seen as useful information in some specific definition? You are adding another conditional but nested conditionals still all rely on the first. We are getting 1 bit of data:0|1; from this entrangled pair. Fleet1 has Strategy0 in case their measurement reads 0. Strategy0 requires Fleet2 to act using Strategy2 for the highest probability of success. Fleet1 also has Strategy1 in case their measurement reads 1. If Strategy1 also requires Fleet2 to act using Strategy2 for highest probability of success then Fleet1's measurement is useless as Fleet2 can just use Strategy2 in both events. If instead Strategy1 requires a new Strategy3, and even though you could communicate which of these strategies to choose faster than we know how to communicate that electromagnetically, our 1 bit of information is still useless because you would still have to prepare for both eventualities. Both pairs: Strategies02 and Strategies13; would equally have to have the same probability of success because if one is favoured over another then using this technique to decide your fleet movements could result in your allowing the possibility for the measurement to order you in a strategy you know is less likely to be successful. This is what I was trying to get at by using the word 'desirable'. Fleet2 may appear to be waiting on Fleet1 for orders, but in fact both fleets are waiting on their orders from the first measurement.

qbutt 5y ago

This talk is excellent. Thank you for that. I think an issue with communicating the lack of information transmission is that the statement usually fails to acknowledge two aspects: 1) We are unable to reliably force any one entangled particle to a specified state prior to measurement. ( You mention this more passively in a gp >"First of all, we don't know which color is in which envelope at the start." ) 2) After measuring we have now entangled our particle to our measurement. So, if after our measurement we change the state of our particle the previously entangled particle fails to reliably correlate. Information is transmitted; it's useful information that we are unable to communicate. If I give you instructions saying if the envelope contains this then do this or if it contains that then do that, you can use the information from the particle's entanglement to make that decision, but because of 2) you can only use it to make that decision reliably once, and because of 1) those two outcomes will have to be equally desirable for this form of communication; making it useless. Just roll a dice.

zelphirkalt 5y ago
Couldn't one argue, that in some situations coordination via previously agreed upon criteria is worth more than which one of two decisions is made? If A and B agree upon, that B will know what A is doing in either case of discovery, then B needs only to look at their observation and will know what A's observation is (the opposite). Then B can know how A will act, because A decides what to do based on what they observe. Then B can act in a coordinated way. Even though it is only a roll of a die, it can still be helpful. For Sci-Fi example: Some alien spaceship fleet (bare with me!) wants to attack another civilization from 2 sides across wast distances. They split up waaay before that and each keeps an entangled particle. They agree upon which observation means what detail in the first fleet's attack plan. Depending on that, the second fleet will act differently on the other side. But the first fleet only decide which of the 2 strategies to use, when they are already split up, based on the observation of the entangled particle. The second fleet has to act accordingly, or the strategy will fail. Is this impossible? Or is this simply not seen as useful information in some specific definition?
- ahelwer 5y ago
  You can accomplish the same thing with a PRNG initialized to the same seed.
- qbutt 5y ago
  > Or is this simply not seen as useful information in some specific definition? You are adding another conditional but nested conditionals still all rely on the first. We are getting 1 bit of data:0|1; from this entrangled pair. Fleet1 has Strategy0 in case their measurement reads 0. Strategy0 requires Fleet2 to act using Strategy2 for the highest probability of success. Fleet1 also has Strategy1 in case their measurement reads 1. If Strategy1 also requires Fleet2 to act using Strategy2 for highest probability of success then Fleet1's measurement is useless as Fleet2 can just use Strategy2 in both events. If instead Strategy1 requires a new Strategy3, and even though you could communicate which of these strategies to choose faster than we know how to communicate that electromagnetically, our 1 bit of information is still useless because you would still have to prepare for both eventualities. Both pairs: Strategies02 and Strategies13; would equally have to have the same probability of success because if one is favoured over another then using this technique to decide your fleet movements could result in your allowing the possibility for the measurement to order you in a strategy you know is less likely to be successful. This is what I was trying to get at by using the word 'desirable'. Fleet2 may appear to be waiting on Fleet1 for orders, but in fact both fleets are waiting on their orders from the first measurement.