tag:blogger.com,1999:blog-26741618.post6325216597998067302..comments2024-02-28T02:22:20.886-08:00Comments on homunculus: Not so spookyPhilip Ballhttp://www.blogger.com/profile/09986655706443117158noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-26741618.post-15695706633771175972017-06-19T00:51:20.414-07:002017-06-19T00:51:20.414-07:00Yes, we must talk about this some day George. It&#...Yes, we must talk about this some day George. It's certainly a puzzle how to talk about these correlations, but personally I don't see all versions of Copenhagen as mysticism opposed to materialism. One could of course argue, as Bohr did, that the purpose of physics/science is to provide predictions of what we'll see, and quantum mechanics does that. And even if there's action at a distance (though I see no need to invoke it), it's not clear how it can possibly be causal - I don't even know what superluminal causality could mean...Philip Ballhttps://www.blogger.com/profile/09986655706443117158noreply@blogger.comtag:blogger.com,1999:blog-26741618.post-78269029534281615082017-06-15T15:54:04.685-07:002017-06-15T15:54:04.685-07:00Hi George,
Thanks for your comments. I know you’ve...Hi George,<br />Thanks for your comments. I know you’ve thought about this carefully, so I certainly want to think about your remarks carefully too. But I can say a few things right away.<br /><br />First, I’ve given you the wrong impression about what I’m saying about Einstein. When I say “Einstein’s spooky action at a distance”, I mean “the thing that Einstein spoke about”, not “the thing that Einstein believed in”. Of course he didn’t believe in it. That was the whole point: the fact that he regarded the EPR experiment as requiring it, in the Copenhagen view, was why he thought the Copenhagen view was wrong.<br /><br />Second, I have somewhat too casually conflated hidden-variables theories and local realism. That’s because Einstein’s HV view was, I believe it is fair to say, a local realist one. Today folks are talking about nonlocal HVs, but I don’t think Einstein ever contemplated such a thing. And so my point is that Einstein was implicitly assuming local realism all along – which is why he figured that the Copenhagen view could only preserve the correlations by some kind of action from one particle to the other.<br /><br />I don’t see why action at a distance is forced on Copenhagen (with or without collapse) – and neither did Bohr, of course. As I say, the standard Copenhagen view today (to the extent that one can speak about such a thing at all) invokes nonlocality – so you don’t need anything to “get” from one particle to the other. David Mermin said it very clearly: the mystery of the EPR experiment is that “it presents us with a set of correlations for which there is simply no explanation”.<br /><br />You’re clearly unhappy with “no explanation”, which is why you’re not ruling out some sort of “hidden causation”. I guess this shows you’re a local realist at heart. But why shouldn’t the world be nonlocal at this level? After all, there are folks looking for simple physical axioms out of which quantum nonlocality will fall quite naturally. It seems entirely possible to me that they’ll find them. And don’t the Bell tests anyway make it impossible to sustain both locality and realism?<br />Philip Ballhttps://www.blogger.com/profile/09986655706443117158noreply@blogger.comtag:blogger.com,1999:blog-26741618.post-85899534738627507512015-09-01T03:20:16.057-07:002015-09-01T03:20:16.057-07:00The word you are looking for is causality. There i...The word you are looking for is causality. There is non-locality indeed, but no causal connection.Anonymoushttps://www.blogger.com/profile/07215604187551098427noreply@blogger.com