http://www.molecularassembler.com/KSRM/3.16.htm

Freitas neglected to piont out that a working model was presented to the patent office before the patent was allowed. Your corrupt government at work!

Charles Michael Collins

the Cornell replicator is as well infringing, you can see here at:
http://leenks.com/link15145.htm

http://www.islandone.org/MMSG/aasm/

the new report is just another mechanism by which we might accomplish the same thing

Have you ever taken a detailed look at any manufacturing process?

No, not really. This is similar to but distinct from a manufacturing process: for example, at least at this point, we are not concerned with the economics of the self-replication process. This has many ramifications: for example, rejection rates become less important (you don't necessarily care if the replicator make 99 duds for every functional daughter replicator if you don't care about the cost, providing the initial device has a probabilistic lifetime such that on average it will survive long enough to reproduce).

Have you ever taken a detailed look at embryology?

I took two semesters of developmental bio as an undergrad. I was near the top of the class first semester, at the top the second. But I think that the biological analogy, while relevant, can be pushed too far. Replicating systems needn't look like multicellular organisms. Recall the Lackner-Wendt proposal of a few years back, for example. ("Exponential growth of large self-reproducing machine systems," by Klaus S. Lackner and C. H. Wendt, Math. Comput. Modelling Vol. 21, No. 10, pages 55-81, 1995.)

…go ahead, squint your eyes and picture yourself in a world where such concepts will not impede your fantasies.

I'm more interested in trying to extract the relevant parameters from the sea of possibilities; that's a key part of modelling. You haven't provided any evidence that the issues you raise are of any quantitative importance in this situation. It would be nice if the authors had addressed some of those issues themselves, but again, that's not necessarily a fatal flaw in preliminary work.

Have you ever taken a detailed look at any manufacturing process? The concepts of yield, failure, rework, and discard are inherent to any real-world manufacturing process. Have you ever taken a detailed look at embryology? The concept of apoptosis is inherent to the buidling of any multicellular organism. But go ahead, squint your eyes and picture yourself in a world where such concepts will not impede your fantasies. Knock yourself out.

The phenomena which you mention all have natural timescales associated with them: damage rates, error rates, senescence, etc. The self-replication process itself has a characteristic time, namely, the time required for replication to occur (and for the newborn replicator to grow to maturity, if it is not produced in a replication-competent state). So the question is, are any of the failure rates "fast" compared to the replication time? If not, one usually can ignore them, at least to a first approximation.

My impression from skimming the paper is that that's what the authors did: there was no compelling reason to think failure (whatever its probability distribution) was fast compared to replication, so they didn't worry about it. For a preliminary study – as opposed to a final design – that's not unreasonable. Obviously, subsequent studies should address the issues you raise. But to insist that the original study is without merit ("fatally flawed") because of this omission, without pointing out a single concete example of something likely to fail so fast that it could be expected to kill most replicators before they replicate, is unreasonable, and suggests prior bias.

If you don't see the connection, then you do not understand the problem space. The problem space is rife with concepts such as damage, interference, error, rework, repair, apoptosis, senescence, quality assurance, quality control, and on an on. If you squint your eyes and look sideways you can manage not to see these real-world considerations, and that is the tack the authors of the study have taken.

I don't understand. Are you saying that damage control, and words therein related, must exist within a feasability study concerned only with technical aspects of just getting the nanomachines built in the first place?

I see no required connection, myself.

Well survey of the field and their conclusions are reasonable.

I searched the NASA report in vain for the words "cull," "damage," and "apoptosis." In the absence of the overarching concept of damage control typified by such terms I beleive the study is a useless exercise in self-delusion. Your mileage may vary.