Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 beta 3/9/83; site frog.UUCP Path: utzoo!linus!philabs!cmcl2!seismo!harvard!think!mit-eddie!cybvax0!frog!john From: john@frog.UUCP (John Woods) Newsgroups: net.physics Subject: Re: Michelson Morley experiment Message-ID: <229@frog.UUCP> Date: Tue, 16-Jul-85 12:04:16 EDT Article-I.D.: frog.229 Posted: Tue Jul 16 12:04:16 1985 Date-Received: Sat, 20-Jul-85 16:30:14 EDT References: <392@sri-arpa.ARPA> Organization: Charles River Data Systems, Framingham MA Lines: 32 > From: Doug Gwyn (VLD/VMB) > The field of a bar magnet is due primarily to aligned nuclear spins > (actually, there are lots of magnetic "domains" each with aligned > nuclei), not electron spins, if I recall my solid state courses > correctly (it's been a long time). This doesn't affect your > ether proposal in any significant way, though. My solid state physics books are at home, but my trusty Eisberg & Resnick here ("Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles, and New Coke, Whipped Cream, ....") has the following to say: "In a paramagnetic material the atoms contain permanent magnetic dipole moments. These moments are associated with the intrinsic electron spin and the orbital motion of the electrons. (Nuclear magnetic dipole moments are three orders of magnitude smaller than the electronic magnetic dipole moments ...)" Later it explains that ferromagnetism is (roughly) a special case of paramagnetism, where partially filled 3d (or 4d) inner subshells allow the atoms to conspire to align their electron spins with each other. I'd go into further detail from it, rather than spouting my own misrememberings, but I've been berated previously for doing that. Some people are never happy. If you can find Eisberg&Resnick, I recommend it as a good introductory text. (Well, I liked it, anyway). It attempts to provide a general overview of Quantum Physics to prepare you for "the next" course in rigorous Quantum Mechanics. -- John Woods, Charles River Data Systems, Framingham MA, (617) 626-1101 ...!decvax!frog!john, ...!mit-eddie!jfw, jfw%mit-ccc@MIT-XX.ARPA I have a bad habit of thinking of tremendously witty .signatures just before I fall asleep. If I kept paper by my bed, you'd probably be laughing uncontrollably at this very moment. Sorry.