Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!akgua!sdcsvax!sdcrdcf!hplabs!sri-unix!crummer@AEROSPACE
From: crummer%AEROSPACE@sri-unix.UUCP
Newsgroups: net.physics
Subject: Re:  Dean Drive Possible?
Message-ID: <683@sri-arpa.UUCP>
Date: Sat, 12-May-84 23:03:11 EDT
Article-I.D.: sri-arpa.683
Posted: Sat May 12 23:03:11 1984
Date-Received: Mon, 14-May-84 01:05:11 EDT
Lines: 23

From:            Charlie Crummer <crummer@AEROSPACE>

     Date:     Fri, 27 Apr 84 16:01:48 EST
     From:     Doug Gwyn (VLD/VMB) <gwyn@Brl-Vld.ARPA>
     Subject:  Re:  Dean Drive Possible?
     
     It is supposedly possible to change one's orientation by an appropriate
     series of internal motions, but not one's angular momentum (conservation
     of which is a direct consequence of rotational symmetry of the fundamental
     laws).

If by change in orientation you mean the angle swept out by some orientation
vector during the orientation change then this angle is proportional to the 
time integral of the angular momentum of the system with respect to some 
reference.
When the angular momentum is constant the orientation is changing at a constant
rate unless the orientation vector is aligned with the axis of rotation in 
which case the proportionality constant is zero.  When the direction of
something, e.g. a telescope, on a satellite is changed it is sometimes done,
at the expense of a compensating change in the opposite direction of something
else, by "gyro torquing".  Is this the "internal motion" you mean?
  
  --Charlie