On Thu, 1 Jan 2004, Tim May wrote:
A few moments of thought will show the connection between replicators
and general assemblers. A general assembler can make another general
assembler, hence all general assemblers are replicators. And in fact
this is necessary to make mechanosynthesis nanotech viable, as
otherwise it takes all the multibillion dollar wafer fabs in the world,
if they could make nanoscale things, to make some scum on the bottom of
a test tube.
Or a few-dollar fermentation tanks with suitable bacteria, once its genome
is tweaked in required way. Who ever said that the nanoparticles we need
can't be proteins or organic molecules with required shape/properties? If
viral particles can self-assemble from host-cell-synthetized proteins, if
complicated structures like bacterial propulsion systems - or even whole
plants - can be formed, why not nanomechanical systems? Why bother with
assembling machines when they could be grown?
I hope I didn't screw up my understanding of "nanosynthesis". If it is
"build anything you want by telling the general assembler", then this
won't work and would need a lab; but for mass-producing nnoparticles, eg.
surface coatings or elements for camera or memory arrays, biotech should
be good enough.
Which is why I was careful to say "mechanosynthesis" and even to qualify the type of replicator as "Drexler-style."
We've had systems which can replicate in 25 minutes or so for as long as we've existed. But making bread is not the same thing as making computers, or Boeing 747s, or non-bread kinds of food.
Specialized biologicals making specialized things is probably where "nanotechnology" will be a commercial success, but it just ain't real nanotech.
--Tim May
