Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!akgua!mcnc!decvax!harpo!seismo!hao!hplabs!sri-unix!gwyn@Brl-Vld.ARPA From: gwyn@Brl-Vld.ARPA Newsgroups: net.physics Subject: Re: Dean Drive Possible? Message-ID: <715@sri-arpa.UUCP> Date: Mon, 14-May-84 05:41:38 EDT Article-I.D.: sri-arpa.715 Posted: Mon May 14 05:41:38 1984 Date-Received: Wed, 16-May-84 03:24:43 EDT Lines: 15 From: Doug Gwyn (VLD/VMB) No, what I had in mind was more like this: A space-suited person in outer space holds two massive dumbbells. He takes turns holding them asymmetrically at different distances and waving them around. After a while the dumbbells are in their original positions w.r.t. the person but he is now facing some direction different from the one he started out facing. I am not sure that this scenario is actualizable; it was told to me during a discussion of the Dean Drive and freely-falling cats. Supposedly someone determined that it was possible for a cat to reorient itself without reacting against the air. I would be skeptical except that I haven't been able to come up with a quick counter-proof (the problem is that the inertia tensor is not constant).