Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!clyde!rutgers!ames!ptsfa!pbhyc!djo From: djo@pbhyc.UUCP Newsgroups: sci.philosophy.tech,sci.physics Subject: Aspect Experiment and Meaning of QM Message-ID: <650@pbhyc.UUCP> Date: Mon, 25-May-87 21:16:28 EDT Article-I.D.: pbhyc.650 Posted: Mon May 25 21:16:28 1987 Date-Received: Tue, 26-May-87 04:41:01 EDT References: <1275@cci632.UUCP> <766@klipper.cs.vu.nl> Reply-To: djo@pbhyc.UUCP (Dan'l Oakes) Organization: Pacific * Bell, San Ramon, CA Lines: 47 Keywords: aspect light faster Xref: utgpu sci.philosophy.tech:68 sci.physics:1378 In article <766@klipper.cs.vu.nl> biep@cs.vu.nl (J. A. "Biep" Durieux) writes: >Now jump into your car and follow one of those half-wits. After some >time you overtake it, grab your magnifying glass, and (the magic word >in QM) *observe* that the particle spins left (say). At this very same >moment, at some far distance, the wave-function for the other half-wit >collapses into the description of a right-spinning particle. So the >information that you observed your particle must have travelled in >zero time to the other half-wit. FTL information transfer. > >Perhaps one of the philosophical physicists can comment on this? >(If they aren't already bored of it, for it keeps popping up in their >newsgroup, I believe.) This is an ontological problem that I see again and again. Physicists become so used to manipulating equations that they confuse them with the particles they describe. The wave-furction for a particle is not the particle; it is not even the wave-like behavior of the particle; it is a _descriptor_ of the wave-like behavior of the particle, and exists only within the context of a system which can process the "language" in which the wave-function is written. In other words, THE MAP IS NOT THE TERRITORY. The wave-function for the half-wit contains both possibilities (left-spinning and right spinning) BECAUSE you have not observed the particle. The particle has been spinning very happily left all along. The wave-function does not describe the particle; it describes what you know (or, more exactly, what you _can_ know without observation) about the particle. The particle, however, does not care that it has been observed. It goes right on spinning as if you had observed nothing. Likewise, the other half-wit has been spinning right all along. The collapse of the wave-function, which exists only in the mind of the observer, affects it not one whit, and nothing has travelled from you to it. Nor has anything travelled from it to you; you know something about it that you did not know before -- the direction of its spin -- but you already knew that its spin was opposed to that of the half-wit you were following. To believe that its spin was determined by your observation of the primary half-wit is sheerest anthropocentrism: the belief that the universe must conform to the state of Man's knowledge. The best reply to that belief was, and remains, Sir Arthur Eddington's famous remark that "the universe is not only queerer than we imagine -- it is queerer than we can imagine." Or words to that effect; I'm quoting from imperfect memory.