Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/17/84; site bcsaic.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!ssc-vax!bcsaic!michaelm From: michaelm@bcsaic.UUCP (michael b maxwell) Newsgroups: net.physics Subject: Re: Do Positrons Have Negative Mass? Message-ID: <228@bcsaic.UUCP> Date: Wed, 21-Aug-85 16:33:47 EDT Article-I.D.: bcsaic.228 Posted: Wed Aug 21 16:33:47 1985 Date-Received: Sun, 25-Aug-85 03:56:51 EDT References: <437@ttidcb.UUCP> Reply-To: michaelm@bcsaic.UUCP (michael b maxwell) Organization: Boeing Computer Services AI Center, Seattle Lines: 38 Summary: In article <437@ttidcb.UUCP> jackson@ttidcb.UUCP (Dick Jackson) writes: > >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? I read in the newspaper about a week ago that someone (Stanford??) was doing research on the mass of antimatter (not specifically positrons). The article stated that NASA was interested in this peripherally--they wanted to know whether antimatter could be contained, in the hopes that *it could be used as a fuel in spaceships*. Shades of Star Trek!! Can this really be? Or are the newspapers up to their often bad standard of journalism? :-) On a more morbid note, suppose antimatter could be contained, presumably in an electric field inside a vacuum bottle. Off hand, it seems that such an apparatus could be very small--perhaps briefcase sized. It wouldn't take very much antimatter to make a very powerful bomb. (Did I read that something like a gram of matter gets converted into energy in a nuclear bomb blast?) Let's hope that antimatter remains extremely difficult to produce. (Has more than a microgram ever been produced in all the world? I have no idea, but from what I hear even the largest accelerators produce only a few 100,000 antimatter particles?? At that rate, we're safe for a long time...) Of course, another problem with the idea of an antimatter terrorist bomb is that no vacuum bottle is perfect, and the antimatter would be a constant source of radiation as matter leaking in encountered the antimatter. Perhaps too much radiation to safely carry around? I hope so... Does anyone have a handle on the math of this? -- Mike Maxwell