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Can anyone explain what is the usual expalnation for what happens when two entangled particles are measured? That is, if one of the particles is measured, and t

• bowsamic 4y ago
  > Can anyone explain what is the usual expalnation for what happens when two entangled particles are measured? In the most extreme case of entanglement, the two systems cannot be described separately, but only by some coupled state. I.e., if you have two particles that can be spin up or spin down, you either find them both spin up, or both spin down as an example. That means, if you measure the spin of particle 1 you already know the spin of particle 2. We interpret this as the measurement affecting the other particle instantaneously even though they may be spatially separated. More generally, entanglement just means that there is an extremely strong correlation between the two systems. > That is, if one of the particles is measured, and the other is not, what happens to the second one? Is there some time where the second particle is still entangled to the first one or is it going to be entangled until measured? There is immediately no longer any entanglement after one of the particles is measured. If you measure the same observable again you will get the same result, and if you measure an observable incompatible to that observable on one particle you will not affect the other particle.