X-Message-Number: 11196 Date: Sat, 30 Jan 1999 07:54:42 -0800 From: "Joseph J. Strout" <> Subject: [off-topic] more on the case of the missing ETs Brook Norton <> wrote: >I also believe it is possible that all technologically advanced societies >eventually stumble on some very fundamental, very deadly technology, like >gray-goo or something along these lines. In this case, all societies are >eliminated at the same stage of their development and so again, they are >invisible to us. I hope this scenario doesn't pan out! Yes -- I've been pondering Fermi's Paradox for many years, and recently have had some hope because of gamma ray bursts (GRBs). These are massive outpourings of energy concentrated into a few seconds, visible from clear across the universe. It's recently been calculated that such a burst, if it happened in a galaxy like ours, would likely kill all surface life in the galaxy (i.e., only life under water or rock might be protected). It's also been calculated that such bursts should happen every few hundred million years per galaxy. This affects the Fermi Paradox in two ways. First, it may be that life in the galaxy gets substantially reset every few hundred million years. So instead of counting from the formation of the galaxy, something like 10 billion years ago, we should count from the last GRB, perhaps only hundreds of million years ago. In that case, there may be several (perhaps many) civilizations now achieving interstellar technology, which have not yet had time to colonize the whole galaxy (nor to reach some form so advanced they appear to leave our universe). Alternatively, since no one knows what causes GRBs (it requires such violent events as two colliding black holes), it may be that these are industrial accidents or weapons -- the very, very deadly technology suggested by Brook. I don't know if anyone has calculated what would happen within a few tens of light-years of ground zero in a GRB, but I suspect it would entirely wipe out even an advanced technological civilization. So perhaps that's what's happening. But like Brook, I hope this is not the case! We now return you to your regularly scheduled discussion of cryonics... Cheers, -- Joe ,------------------------------------------------------------------. | Joseph J. Strout developer: MacOS, Unix, 3D, AI | | http://www.strout.net | `------------------------------------------------------------------' Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=11196