Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84 exptools; site ihlpg.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxn!ihnp4!ihlpg!tan From: tan@ihlpg.UUCP (Bill Tanenbaum) Newsgroups: net.physics Subject: Re: Do Positrons Have Negative Mass? Message-ID: <1115@ihlpg.UUCP> Date: Wed, 21-Aug-85 18:20:32 EDT Article-I.D.: ihlpg.1115 Posted: Wed Aug 21 18:20:32 1985 Date-Received: Sat, 24-Aug-85 15:02:33 EDT References: <437@ttidcb.UUCP> Organization: AT&T Bell Laboratories Lines: 21 > There's a discussion on net.scifi-lovers relating to negative mass - > the hope is to produce an FTL drive somehow. This triggered off a > memory and I'm hoping someone can contribute. > > In about 1966 I attended a seminar by Prof. Fairbanks who researched > at Stanford U (I think). He was trying to slow down positrons for long > enough to tell if they fell upwards or downwards. > > Does anyone know how this turned out? If this experiment did not get > completed, has there been any other work? -------------------- The existence of negative mass (i. e. mass that falls up) would blow general relativity out of the water as it violates the equivalence principle. Also, the equivalence of gravitational and inertial mass has been shown experimentally to great accuracy (I can't remember the experimental error). I don't know whether anyone has directly experimentally determined that positrons fall down, but if they don't it would be a great shock to all physicists, expecially to the one doing the experiment. -- Bill Tanenbaum - AT&T Bell Labs - Naperville IL ihnp4!ihlpg!tan