X-Message-Number: 21613 Date: Thu, 17 Apr 2003 10:15:52 -0400 From: Thomas Donaldson <> Subject: CryoNet #21605 - #21611 Hi everyone! For Francois and Bryan Hall: A good point about fantasies regarding a singularity. (We may someday look like Gods to people as primitive as we are now, but we will never actually BE Gods... we will always run up against things we cannot do, at least when we meet them). In any case, an interesting general movement seems to be happening in thoughts about other intelligences elsewhere. One it was thought that the Galaxy contained many more abodes for complex life than it is now believed; the latest stinker here comes from thoughts about what the discovery of so many hyperJupiters may mean: if a star is even a little younger than the Sun, a Jupiter with much more heavy elements forms, swallowing up all the other planets in its system because it grows faster than our Jupiter. If the star is a bit younger, it can't form planets big enough to support evolution of intelligent life. There are other problems too. The point here is simply that whenever we can look at the problem more closely, we find even more limitations on the number of possible places where intelligent life could evolve. These problems look to me like they will continue to occur: the locations for intelligent life get scantier and scantier. There's another issue too: consider the time that intelligent life may require to develop, and treat it statistically as a bell-shaped curve. Then it may easily happen that most planets don't grow intelligent life forms simply because they don't remain hospitable to life for long enough that the bell-shaped curve comes into play ie. most stars only provide habitats for the time needed to get the very lowest part of the bell curve. Without human interference, the Earth will become uninhabitable some time before the Sun even leaves the Main Sequence and ceases to be a G-Type star. Why? Because it has been slowly growing brighter. (We can always move the Earth, but if a planet lacks INTELLIGENT life, that won't happen). If you want to read about the theories kicked off by the discovery of many hyperJupiters, SCIENTIFIC AMERICAN had several articles in about 2000. (More exact references later if requested... together with references to ICARUS, a scholarly astronomy journal with looks at such things). Best wishes and long long life for all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=21613