= 27d567bc2d48d9f40e9ccc20ea370b15)
tut comments on Open Thread: February 2010 - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (738)
Yes. They only appear weird if you look at small enough scales, but classical electrons would not have stable orbits, so without quantum effects there'd be no stable atoms.
No, but there is evidence. There is a proof that if they were caused by something unknown but deterministic (or if there even was a classical probability function for certain events) then they would follow Bell's inequalities. But that appears not to be the case.
But this is where things get really shaky for materialism. If something cannot be explained in X, this means there is something outside X that determines it.
Materialists must hope that in spite of Bell's inequalities, there is some kind of non-random mechanism that would explain quantum events, regardless of whether it is possible for us to deduce it.
Alicorn asked above:
In principle, you can't. And one of the foundational (but non-obvious) assumptions of materialism is that nothing is truly random. The non-refutibility of materialism depends upon never being able to demonstrate that something is actually random.
Later edit: I realize that this comment is somewhat of a non-sequitur in the context of this thread. (oops) I'll explain that these kinds of questions have been my motivation for thinking about Newcomb in the first place. Sometimes I'm worried about whether materialism is self-consistent, sometimes I'm worried about whether dualism is a coherent idea within the context of materialism, and these questions are often conflated in my mind as a single project.
In that case I am not a materialist. I don't believe in any entities that materialists don't believe in, but I do believe that you have to resort to Many Worlds in order to be right and believe in determinism. Questions that amount to asking "which Everett branch are we in" can have nondeterministic answers.
No worries -- you can still be a materialist. Many worlds is the materialist solution to the problem of random collapse. (But I think that's what you just wrote -- sorry if I misunderstood something.)
Suppose that a particle has a perfectly undetermined choice to go left or go right. If the particle goes left, a materialist must hold in principle that there is a mechanism that determined the direction, but then they can't say the direction was undetermined.
Many worlds says that both directions were chosen, and you happen to find yourself in the one where the particle went left. So there is no problem with something outside the system swooping down and making an arbitrary decision.
Those sorts of question can arise in non-QM contexts too.
Or, of course, the causes could be non-local.
What are Bell's inequalities, and why do quantumly-behaving things with deterministic causes have to follow them?
Alicorn, if you're free after dinner tomorrow, I can probably explain this one.
Um... am I missing something or did no one link to, ahem:
http://lesswrong.com/lw/q1/bells_theorem_no_epr_reality/
Thank you, although I find this a little too technical to wrap my brain around at the moment.
The EPR paradox (Einstein-Podolsky-Rosen paradox) is a set of experiments that suggest 'spooky action at a distance' because particles appear to share information instantaneously, at a distance, long after an interaction between them.
People applying "common sense" would like to argue that there is some way that the information is being shared -- some hidden variable that collects and shares the information between them.
Bell's Inequality only assumes there there is some such hidden variable operating locally* -- with no specifications of any kind on how it works -- and deduces correlations between particles sharing information that is in contradiction with experiments.
* that is, mechanically rather than 'magically' at a distance
Well, actually everything has to follow them because of Bell's Theorem.
Edit: The second link should be to this explanation, which is somewhat less funny, but actually explains the experiments that violate the theorem. Sorry that I took so long, but it appeared that the server was down when I first tried to fix it, so I went and did other things for half an hour.
There's no good explanation anywhere. :(