kube@cogsci.berkeley.edu (Paul Kube) (05/26/87)
In article <650@pbhyc.UUCP> djo@pbhyc.UUCP (Dan'l Oakes) writes: >In article <766@klipper.cs.vu.nl> biep@cs.vu.nl (J. A. "Biep" Durieux) writes: >>... So the >>information that you observed your particle must have travelled in >>zero time to the other half-wit. FTL information transfer. <Applause> > >... Physicists >become so used to manipulating equations that they confuse them with >the particles they describe. >... The particle >has been spinning very happily left all along. OK, it's time somebody brought up Bell. Starting from the assumption that there is no superluminal linkage in your apparatus and that particle pairs are in definite states while unobserved, relationships among probabilities of observed particle state conditional on apparatus configuration are entailed. It's too sad for words, but certain of these relationships (Bell-type inequalities) are strongly contradicted by experiment. So, everybody, what do you want to give up: the impossibility of FTL information transfer, that the particle was spinning happily left all along, or the relevance of mathematics for physics? Oakes sounds like he might opt for doing without the last, but it's interesting to note that the Bell inequalities don't depend on the formalism of quantum mechanics at all (though QM does correctly predict the observed probabilities). --Paul kube@berkeley.edu, ...!ucbvax!kube
flink@mimsy.UUCP (05/27/87)
kube@cogsci.berkeley.edu.UUCP (Paul Kube) writes: >So, everybody, what do you want to give up: the impossibility of FTL >information transfer, that the particle was spinning happily left all >along, or the relevance of mathematics for physics? Good question; here's another: if we take the second option, what are the philosophical implications, if any? Might we take the Aspect et. al. experiments to show merely that, at least in the case of "spin" etc., we have picked the wrong concepts with which to describe the real world? By the way, I think you should say "FTL causal influence" rather than "FTL information transfer". The collapse of a wave-packet in the Aspect experiments, even if interpreted as involving FTL causal influence, would not be useful for communication. I'll let a more QM-fluent netter explain why. Please direct followups to whichever group(s) are appropriate, and only those. -- Paul Torek flink@mimsy.umd.edu
biep@klipper.UUCP (05/27/87)
In article <766@klipper.cs.vu.nl> biep@cs.vu.nl (J. A. "Biep" Durieux) writes: >... So the information that you observed your particle must have travelled >in zero time to the other half-wit. FTL information transfer. <Applause> In article <650@pbhyc.UUCP> djo@pbhyc.UUCP (Dan'l Oakes) writes: >... Physicists become so used to manipulating equations that they >confuse them with the particles they describe. >... The particle has been spinning very happily left all along. In article <19028@ucbvax.BERKELEY.EDU>, kube@cogsci.berkeley.edu.UUCP (Paul Kube) writes: >OK, it's time somebody brought up Bell. >So, everybody, what do you want to give up: the impossibility of FTL >information transfer, that the particle was spinning happily left all >along, or the relevance of mathematics for physics? >--Paul kube@berkeley.edu, ...!ucbvax!kube Too bad Einstein already has thrown away the ether. Isn't there some other concept we might want to get rid of (other than observer-independent behaviour)? -- Biep. (biep@cs.vu.nl via mcvax) When a doctor doctors a doctor, does the doctoring doctor doctor the doc- tored doctor with the doctoring doctor's doctrine, or does the doctoring doctor doctor the doctored doctor with the doctored doctor's doctrine?