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Path: utzoo!linus!philabs!pwa-b!mmintl!franka
From: franka@mmintl.UUCP (Frank Adams)
Newsgroups: net.sf-lovers
Subject: Re: Meeting Advanced Aliens
Message-ID: <526@mmintl.UUCP>
Date: Tue, 23-Jul-85 13:51:45 EDT
Article-I.D.: mmintl.526
Posted: Tue Jul 23 13:51:45 1985
Date-Received: Thu, 25-Jul-85 21:13:02 EDT
References: <410@ttidcb.UUCP> <15835@watmath.UUCP>
Reply-To: franka@mmintl.UUCP (Frank Adams)
Organization: Multimate International, E. Hartford, CT
Lines: 66
Summary: More possibilities


In article <15835@watmath.UUCP> jagardner@watmath.UUCP (Jim Gardner) writes:
>[...]
>
>Possible answers to the question "Where are the aliens?" (most of
>which have appeared in numerous SF stories):
>[...]
>(f)   FTL travel is impossible.  Inter-stellar travel requires the colony
>      ship approach or suspended animation.  Everything is subject to
>      relativistic effects like time dilation.  This makes exploration
>      much more difficult and time-consuming.  It just so happens we
>      haven't been found yet; indeed, many races may decide that
>      inter-stellar colonization is economically pointless and may do
>      their best to live at home.

See my previous posting; I won't repeat myself here.

>I've probably left out a few explanations from the list.  Variations
>are many; take (c), for example, inter-stellar peace-keepers who prevent
>nasties from interfering.  These could be benevolent beings; malevolent
>beings who wipe out any race that ventures into space; a doomsday ship
>that was programmed by someone to hang around Jupiter and shoot anything
>that happens by; a natural or artificial barrier that makes our region
>of space difficult to enter; and so on.

I would regard nasties as quite different from benevolent protection,
not just a variation.

OK, now for some others:

(h)	Intelligent races at some point evolve past the need for physical
	existence.  As a variation, they find parallel worlds (infinitely
	many of them) and don't need the rest of the universe.

(i)	Intelligent races are inevitably warlike.  At some point they get
	sufficiently deadly weapons and kill themselves off.


However, option (g) seems the most likely to me -- there aren't any other
technological races, at least not in our galaxy.  The next question is,
why not?  The following seem to me to be the main possible reasons:

(1)	Planets which can support life are very rare.  Either planetary
	systems are rare, or the conditions required for life are
	more special than we think.

(2)	Life is a very unlikely phenomenon.  Almost all worlds which
	can support life don't have any.

(3)	Some step in the evolution of intelligent life is very unlikely.
	Maybe multicellular life is unique to Earth.  Maybe sexual
	reproduction is.

(4)	Technology is unique to us.  Other races don't develop it.  This
	may be because they lack appropriate manipulatory organs, or
	because there is something unlikely about its development.

(5)	All of the above.  Perhaps each of the above is 10 to 100 times
	as unlikely as the SETI people estimate, so that the expected
	number of intelligent races in the galaxy is about one.

(6)	Perhaps our evolution was amazingly fast, and we aren't so much
	the only technological species as the first.

(7)	Collisions with astronomical objects may be quite common, and we
	are very lucky not to have been hit by anything really large in
	the last few billion years.