[extropy-chat] Nanoassembly Blueprints using Atomic Resolution MRI

Keith Henson hkhenson at rogers.com
Fri Apr 6 19:58:26 UTC 2007

At 10:19 PM 4/5/2007 -0700, Samantha wrote:

>On Apr 4, 2007, at 4:28 PM, Keith Henson wrote:


>I have doubts about putting  massive numbers of normal body form
>human beings in space.  The technology required to do so changes the
>equations so much is becomes doubtful whether humans or something
>distinctly not today's kind of human would colonize space.
>Supporting a lot of bodies designed for earth conditions does not
>seem optimal.   It is certainly tremendously expensive.   It could be
>done employing telepresence and robotics to build a lot of the needed
>infrastructure and with beanstalks or something much cheaper to get
>out of the gravity well.  But that implies building out technology
>that may make homo saps irrelevant and seriously non-competitive in

You need to remember that this topic was *the* hot technical topic in the 
mid to late 70s.  People such as Eric Drexler put a lot of effort into the 
design and economic studies.  *Given* an industrial seed in space, the cost 
falls very rapidly.  You can achieve some truly remarkable economic effects 
in space.  The prime "figure of merit" for industrial machines in space is 
how rapidly they make their own mass in product.

One of the papers Eric and I presented was for a solar powered metal boiler 
suitable for depositing thick metal on objects with dimension in the km range.

Most of the mass was for the solar concentrator which in space is not very 
heavy.  There were a lot of considerations in the design because the boiler 
was operating *really* hot and you had to deal with such things as 
re-depositing carbon which had evaporated off the solar absorber surfaces.

But the analysis made the case that such a gadget could deposit its own 
mass in aluminum or iron in *8 hours*.  (There was a lot more to the 
subject of making living area because of fracture mechanics.  This is 
covered in the vapor phase fabrication paper.)


>For that matter, why should you choose to keep a body configuration
>that requires such primitive forms of energization as digestion and
>elimination cycles?

I don't know.  The discussion of such questions rapidly drifts into the 
extended Fermi question.  "Why don't we see the engineering works of 
advanced civilizations?"

There are none in our light cone (that we have seen so far) which leaves 
the possibility that we are the only outpost of intelligent life.  The 
alternative is that every one of the technophilic species that arises goes 
down some kind of rat hole and leaves no physical traces in the 
universe.  I frankly don't know what to think, but I suspect a very short 
existence for an evolved creature who learns how to reach inside and tweek 
his pleasure knob.  Minsky had a good deal to say about this in his 
previous book.


> > There is good exciting and bad exciting.  Unfortunately, the odds are
> > stacked by the long evolutionary history of our species against the
> > future being good.
>Yes.  It could be argued that any evolved species is likely to have
>evolved many counterproductive traits making its successful emergence
>into and beyond technological singularity extremely unlikely.   This
>is probably part of the answer to "Where are the aliens?"   They
>didn't make it past this stage.

If they didn't chances we will are very poor.  But that wasn't what I was 
thinking about here.  We live in an era where massive engineering works to 
extract energy and turn it into food have resulted in a population much 
larger than is sustainable on the current technological base.  The "peak 
oil" pinch I think is very likely to set off wars since that is the evolved 
mechanism whereby human populations were reduced to the level the 
environment could feed them.

> > But if you want to do something to improve the odds of a bright
> > future, I
> > have a number of suggestions.  Even so, the most likely number for
> > physical
> > state humans 100 years from now is zero.
>I for one would love to hear some of the suggestions.

Completely independent of global warming, the human race needs something to 
replace carbon fuels.  I have my proposal, SEPS, space elevator/power 
satellites, which is subject to physical and economic analysis.  I am not 
welded to this proposal, and am willing to look at any others.  Propose, 
analyze, and try to get the word out.  If there is a physically sound 
solution that can be implemented, work on getting people to understand it 
and support it.

If people see a bleak future, xenophobic memes will dominate their thinking 
and lead to wars.  We can have our heads in the uploading clouds and it 
won't help a bit when wars disrupt the economy so badly that we starve.

Keith Henson

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