Aleksei
Thanks for the link. It is interesting. Before I started hearing estimates for how common exoplanets were, I thought visits from aliens were a possibility, because I like to have an open mind, but an extremely small one. Now I believe it is a large enough probability that any honest, open-minded person, who is astronomically and technologically reasonably informed, has to consider it sufficiently probable that it deserves thought. The article your link pointed to reinforces that thinking. I disagree with the argument in "The Speed-of-Light Limit Argument," in the left window of the web page, that if aliens could travel no faster than the speed of light, the chance and/or frequencies that they would visit us would be very small. That is because, alien civilizations might have achieved their respective singularity millions or billions of years ago, and with the resultant technology learned how to live and multiply themselves and their supporting technology exponentially in galactic space, so that they would have had more than enough time traveling at sub-C speeds to populate most of the habitable parts of our galaxy. Wikipedia says the Milky Way is 100,000 light years across, and on average 1000 light years thick (other source say it is about 10 times thicker). The would give a volume of roughly 2.5 Trillion cubic light years. I seems reasonable to assumes any advanced, million-years-post-singularity space civilization would be capable of building arrays of extremely large space-based telescopes, each many miles in diameter. If such an array could search for substantially all possibly habitable planets within a 750 light year radius, based first on very accurate measurements of the wobbles of stars, and then from spectrographic information from the light reflected off such planets, themselves --- then it would only take roughly 250,000 such telescope arrays spread throughout the galaxy to check out the entire galaxy for likely habitable planets, since each such telescope could check out one billion cubic light years, each having roughly 8 million stars to monitor in one assumes stars average being 5 million light years appart. As I said, the real interest of this discussion to this AGI list, is that human development of AGI might well affect the alien's attitude toward us --- if they exist and if they are monitoring us --- because it would mean we would be at the start of a rapid technological development that would mean we could become much more equal with them --- making us either more valuable --- or more threatening --- to them. Ed Porter -----Original Message----- From: Aleksei Riikonen [mailto:[EMAIL PROTECTED] Sent: Wednesday, November 26, 2008 12:22 PM To: agi@v2.listbox.com Subject: [agi] Re: If aliens are monitoring us, our development of AGI might concern them On Wed, Nov 26, 2008 at 5:07 PM, Ed Porter <[EMAIL PROTECTED]> wrote: > In my own rather skeptical mind, if I were to make a wild guess I would > currently put the probability of this at roughly at least one in ten, a > large enough possibility that it should, at least, be considered in > discussions of the future of AGI and the singularity. In case there are some on this list that would like a high-quality starting point for getting to know "the ufo scene", the following seems like a good fit: http://www.ufoskeptic.org/ "An information site on the UFO phenomenon by and for professional scientists." Personally, I don't know much about this topic, but that is the highest quality site on it that I've come across, and I recommend it to people who have more motivation than me to learn about UFOs. (Do not infer from the name of the site that it would be dismissing all UFO reports out of hand.) -- Aleksei Riikonen - http://www.iki.fi/aleksei ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?&; Powered by Listbox: http://www.listbox.com ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244&id_secret=120640061-aded06 Powered by Listbox: http://www.listbox.com
