My friends and I got into an argument about determinism, and I brought up that quantum events are random. But I couldn't prove it.
I found the Wikipedia page on Bell's theorem, which seems to imply what I'm trying to show, because it disqualifying local hidden variable models. But I don't understand how the experiment works. I think I understand the steps taken:
- An electron-positron pair is produced, with opposite spins.
- Alice measures the spin of the electron along the x-axis.
- Bob measures the spin of the positron along some axis, which could be the x-axis.
- Alice and Bob compare their results, recording a +1 if their spins match, and a -1 if they do not.
- A graph of "angle between Alice and Bob's axes" vs. "sum of many trials" is created.
The part I don't get is: Why would local hidden variable theories predict a triangular pattern for the graph, and likewise, why would entanglement predict a cosine?