RE: starship-design: It's a bad, bad world out there

[David Levine <david@actionworld.com>]

I think you may be confusing the Drake Equation with the Fermi Paradox.

Before I start, here are two references:

What is the Drake equation?
http://www.landfield.com/faqs/astronomy/faq/part6/section-10.html

What is the Fermi paradox?
http://www.landfield.com/faqs/astronomy/faq/part6/section-11.html

The Drake Equation is the one you mention, which "starts from a set of
assumptions, adds more assumptions to them, then multiplies by still
more assumptions."

The Fermi Paradox, on the other hand, is not an equation.  Fermi, in
fact, started with the Drake Equation, however - before Drake himself
came up with it!  But from there he added the idea of colonization.
Fermi asked how long it would take for a star-faring civilization to
colonize star after star.  How long, he wondered, before they would get
here?  The answer surprised him - even taking vastly conservative
estimates for the speed of expansion of an interstellar civilization
(i.e. fraction of a percent of the speed of light) and assuming a long
"waiting time" at each star - you get an expanding bubble of
civilization that colonizes the ENTIRE galaxy in a few million years.
The assumptions in the Fermi Paradox are very very basic:

1. One civilization arises with the will to colonize.

That's it, the only assumption.  As long as you assume that one such
civilization arose SOMEWHERE in the galaxy before us, we have quite a
quandry: considering the age of the galaxy, why aren't they here?  It
doesn't matter if we use Drake's Equation and come up numbers that say
that the nearest civilization is a thousand light years away.  Because
if only one civilization before us had the will to colonize, they would
have been here already.

We could, of course, be first - but if you accept intelligent life as
being fairly common (i.e. even just a few hundred civilizations in the
galaxy, which is incredibly conservative in some views) this is
statistically unlikely.

In fact, one of the mistakes that most science fiction (not all, mind
you) makes is that any aliens we encounter will be anywhere close to us
technologically.  Basically, there are millions of years of history
behind us, and millions of years of history in front of us.  What are
the odds that another life form we encounter is even within a thousand
years of us on either side?  A million?  If you want to restrict it to
intelligent life forms, really the only direction to go is ahead of us,
because there is even a smaller amount of intelligent history behind us.
If you're talking about a space-faring life form, we can almost
guarantee they will be ahead of us, statistically.  There are around
fifty years of space-faring history behind us, and millions, if not
billions, of years in front of us.

The Fermi Paradox worries me a lot.  Sometimes I really think the only
answer is that we are alone.
-----------------------------------------------------------------
David Levine                                david@actionworld.com
Director of Development               http://www.actionworld.com/
ActionWorld, Inc.                                  (212) 387-8200
"The only reason for time is so that everything doesn't happen at once."