[ExI] extropy-chat Digest, Vol 98, Issue 14

[Kelly Anderson]

On Fri, Nov 11, 2011 at 8:38 AM, Keith Henson <hkeithhenson at gmail.com> wrote:
> As some of you know, I have been working on beamed energy propulsion
> for a number of years.  A recent development is finding a way to get
> into space starting with an airdrop that takes a mass ratio 2 and
> ground based 20 GW of beamed energy to support a half million ton per
> year SBSP construction project.  It's tricky because of the limited
> time (~220 s) the vehicle is in view of the ground station.  The
> effective exhaust velocity is almost 20 km/s.

It's exciting stuff. I'm glad you're working on it!!!

> But in the slightly longer run, the beamed energy source will itself
> be in space.  Because of the longer acceleration time you get from a
> space source, the power can be reduced to 5 GW or less, or the flight
> rate increased.

Cool, I hadn't thought the system through to that point, and that's
really interesting...

> I suspect they will live practically forever and have *no* offspring at all.

In Heinlein's book "Time Enough for Love", that I'm currently reading,
he explains the demise of the original Earth as coming from the fact
that once it is possible to escape Earth, the very best and brightest
among us will be the ones to escape first. Leaving the great unwashed
masses to fend for themselves. It's a kind of "Atlas Shrugged" view
condensed to just a couple of pages... I suspect if space travel does
take off... and founding other worlds does become possible, that Earth
is somewhat doomed to the caprice of the idiots left behind.

Now Heinlein didn't account particularly well for artificial
intelligence, so his vision may be severely short sighted. But you can
see the result of the best and brightest of Europe leaving for
America, so there is an historical precedent for what he proposes. If
you got FTL travel before you got common artificial intelligence, then
I can see his view of the future, but that doesn't look likely. Still
a good read in terms of what do you do with a many thousand years life
span.

-Kelly