>From Message-ID: <3fmkfb$5de@planchet.rutgers.edu> by
nv91-asa@black28.nada.kth.se (Anders Sandberg):
> Jay A. Lewis wrote:
>>If you want nanites to build your house, I'm sure there must be some
>>theoretical limit to how fast this could be done. Each atom will take
>>time to be moved from a supply source to its final destination.
>>Communication between the nanites takes time, their actuators, etc.
>Heat will be the major problem. Moving the atoms to their positions
quickly
>will doubtless release a lot of heat (since their momentum has to go
somewhere
>and they are expected to be at rest when placed in the house). If you
don't
>want the entire construction site to start smoldering, you have to slow
down
>the process. This will also save energy.
I've gotta admit, it's not obvious to me that this is a problem. I'm assuming that the NT house construction will take a few days. When a house is built conventionally, the wood and bricks etc. are all moved, too, and I rarely hear about construction sites catching fire because they were building too quickly. If anything, I would expect a NT-built structure to be more efficient and, hence, less massive.
OTOH, if the individual atoms are going to be plucked from a matrix and then stuck onto another one, waste heat will probably be generated in both processes. This does *not* have a meaningful parallel in conventional construction and could, conceivably, release as much energy as burning all your construction material. If the energy was released over a few days, though, it still probably wouldn't be a problem.
I think I've gone about as far as I can along this line without resorting to math.