I am still thinking about this because it's fun, and I want to say I wrote my two previous posts before reading the entire thread in detail. I've seen that others have been thinking along the same lines as me previously,
@Boing3000 (post 5 and 32),
@Stephen Tashi (post 8 and 10) and of course
@Nugatory in post 26. I'm sorry if I missed mentioning anyone.
Even though I think Bell tests and entanglement experiments are very interesting, I've bypassed commenting on them since as far as I know they are designed specifically to test locality and realism, and not the inherent randomness in quantum mechanical processes.
Let me be more specific what I mean:
In Bell tests, streams of photon pairs are analyzed two by two, and when detected the photons are destroyed.
This means Bell tests are not measuring any random variable of one system/pair of particles only, they are measuring the statistics of many pairs of particles, where one pair of particles are not dependent upon any other pair. I would love to be corrected if I am wrong here.
And this means that my initial setup:
DennisN said:
As an example, assume we have a Stern–Gerlach apparatus with detects the spin of an atom in a vertical direction. If spin down is detected, this generates a 0 in the R sequence, and if spin up is detected, this instead generates a 1 in the R sequence. When n number of atoms have been analyzed we have a R sequence of length n.
also is flawed, since it mentioned measuring the spin of
different atoms. But the spins of different atoms should ideally be completely independent of each other, so this will not be a good randomness test.
To do the randomness test, that is, test the hypothesis that a quantum mechanical process is random, we need to make
repeated measurements on the
same particle/system. The generated sequence would then be the variation of a
single random variable, which then could be statistically and information theoretically analyzed.
One suggestion could be repeated measurements of the spin of
one particle in various directions:
- Measure the spin in the vertical direction. Spin down will generate a 0 in the R sequence and spin up will generate a 1 in the in the R sequence. This will also result in that the horizontal spin now is undetermined.
- Measure the spin in the horizontal direction. Spin left will generate a 0 in the R sequence and spin right will generate a 1 in the in the R sequence. This will also result in that the vertical spin now is undetermined.
- Goto 1 and repeat this many times.
- Then do the analyses as I described in my previous post.
Maybe there's a better way to experimentally do what I am thinking of, and if so, I would love to hear it.
