Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!decvax!harpo!seismo!hao!hplabs!sri-unix!REM@MIT-MC From: REM@MIT-MC@sri-unix.UUCP Newsgroups: net.space Subject: SETI Message-ID: <3346@sri-arpa.UUCP> Date: Fri, 22-Jul-83 11:43:00 EDT Article-I.D.: sri-arpa.3346 Posted: Fri Jul 22 11:43:00 1983 Date-Received: Sun, 24-Jul-83 02:25:54 EDT Lines: 29 From: Robert Elton MaasHere's my view on this. We certainly can't prove life elsewhere impossible until we've examined every little nook and cranney in the Universe, which makes the question moot since at that point we've filled every nook and cranney with our own stuff and probably dumped contamination around which has evolved in strange ways. What we can do is set an upper bound on the extent of life elsewhere, the same way we set upper bounds on other quantities such as deviation from inverse-square law (last I heard F=m1*m2/r^k where k=2.0000000000000 plus or minus some small number in that last place, or somesuch). So far we have shown ETI hasn't conquered Earth in any gross way or jammed our communications. With our next series of experiments we hope to either **FIND** intelligent life elsewhere or set a new upper-bound that on hundreds of nearby stars no major broadcasting such as TV or radar is occurring presently. As years go by we will continue to crank down the limit on life elsewhere or actually discover some out there. It's literally we can't refute the hypothesis "there is life elsewhere", thus that literal hypothesis isn't scientific. But we can refute "The Galaxy is teeming with civilizations as advanced as hours" within the next 50 years, and "The Galaxy is teeming with microscopic life on every little planet that happens to be at the right temperature" within the next few hundred years, or sooner if we get those Alpha Centuri and Epsilon Eridani probes launched in time. Therefore statements about specific amounts of "teeming with life" are indeed scientifically valid. In particular, Sagan's major question, whether there are billions of advanced civilizations in this galaxy or just a handful, can be decided within the next 50 years.