3
votes
2answers
293 views

Determinism loophole?

I was thinking about the question I posted yesterday, and I thought of a better way to ask it. I'm trying to figure out why QM necessitates "pure randomness". Assume you have a photon that has a ...
3
votes
1answer
125 views

(thought) experiment re: Bell's Theorem and Schrodinger's cat

I apologize if this question is naive. I am wondering about what would happen with the following experiment. Start with a standard Bell's Theorem setup: We have two quibits entangled in a particular ...
1
vote
2answers
144 views

Non-locality and Bell's theory

Non-Locality – (just ) one more question? I have read comments that Bell’s theory proves quantum mechanics is non-local, and also comments that it does not. I have read a comment by a very eminent ...
2
votes
1answer
73 views

Is it possible to determine the state or values of something without measuring it

To give context to this question, I am currently looking into non-locality / hidden variables / Bell's Theorem, EPR / etc. I've noticed the assertion that the values / state of something when ...
2
votes
5answers
307 views

How do we know that there isn't a classical solution to the measurement problem/Quantum Mechanical uncertainty?

It was mentioned to me that it can be shown that there is no classical explanation for the uncertainty in Quantum Mechanics -- i.e. that there are no hidden workings that we have just not yet seen, ...
6
votes
2answers
207 views

Bell's Theorem graph

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 ...
0
votes
2answers
125 views

EPR vs. EPRBB? Why can't we perform the original EPR experiment?

The EPR gedanken experiment was invented by Einstein Podolsky and Rosen in 1935. It involved positions and momenta. In 1957, Bohm revised this gedanken experiment into one involving spins, or ...
3
votes
4answers
493 views

How do we show that no hidden variable theories can replace QM?

I've always hit two big stumbling blocks in conceiving of the proof or disproof of hidden variable theories as being even valid idea, let alone an answerable question... I feel I must be ...
8
votes
3answers
954 views

How does Bell's theorem rule out the possibility of local hidden variables?

It seems to be common consensus that the world is non-deterministic and this is proved by Bell's theorem. But even though Bell's experiments proved that the theory of quantum mechanics work, How does ...
1
vote
1answer
204 views

On Bell's Inequality (Classical Intuition) and Quantum Mechanical Counter Intuition

This posting is directly related to the issue in The System and the Measuring Gadget. The QM expectation is given by: $$\langle\sigma_{1}.\vec{a}{\;}\sigma_{2}.\vec b\rangle=-\vec a.\vec b$$ In the ...
4
votes
3answers
627 views

Assumptions in Bell's Theorem

It is often Stated that Bell's Theorem is equivalent to the statement: No theory of Local Hidden Variables can reproduce all of the predictions of quantum mechanics. I see nowhere in Bell's Theorem ...
14
votes
5answers
1k views

What combinations of realism, non-locality, and contextuality are ruled out in quantum theory?

Bell's inequality theorem, along with experimental evidence, shows that we cannot have both realism and locality. While I don't fully understand it, Leggett's inequality takes this a step further and ...