Blah Blah Corner (Chat till your fingers die): - Page 108

Milan Cirkovic of the Astronomical Observatory in Belgrade, points out that the median age of terrestrial planets in the Milky Way is about 1.8 gigayears (one billion years) greater than the age of the Earth and the Solar System, which means that the median age of technological civilizations should be greater than the age of human civilization by the same amount. The vastness of this interval indicates that one or more processes must suppress observability of extraterrestrial communities.

Since at this point, there is no direct and/or widely apparent evidence that extraterrestrial life exists, it likely means one of the following:

We are (A) the first intelligent beings ever to become capable of making our presence known, and leaving our planet. At this point, there are no other life forms out there as advanced as us. Or perhaps extraterrestrial life does exists, but for some reason extraterrestrial life is so very rare and so very far away we'll never make contact anyway—making extraterrestrial life nonexistent in a practical sense at least.

Or is it (B) that many advanced civilizations have existed before us, but without exception, they have for some unknown reason, existed and/or expanded in such a way that they are completely undetectable by our instruments.

Or is it (C) There have been others, but they have all run into some sort of "cosmic roadblock" that eventually destroys them, or at least prevents their expansion beyond a small area.

Since Earth's placement in space and time appears to be unremarkably random, proposition "A" seems fairly unlikely. Assuming humans evolved like other forms of life into our present state due to natural selection, then there's really nothing all that mystical, special or remarkable about our development as a species either. Due to the shear numbers, there are almost certainly other planets capable of supporting at least some form of life. If that is so, then for Earthlings to be the very first species ever to make a noticeable mark on the universe, from a statistical perspective, is incredibly unlikely.

For proposition "B" to be correct would defy all logic. If potentially thousands, or even millions of advanced extraterrestrial civilizations exist in the known universe, then why would all of them, without exception, choose to expand or exist in such a way that they are completely undetectable? It's conceivable that some might, or perhaps even the majority, but for all of them to be completely undetectable civilizations does not seem likely either.

Proposition C in some ways, appears to be more likely than A or B. If "survival of the fittest" follows similar pathways on other worlds, then our own "civilized" nature could be somewhat typical of extraterrestrial civilizations that have, or do, exist. Somehow, we all get to the point where we end up killing ourselves in a natural course of technological development and thereby self-inflict our own "cosmic roadblock".