Re: [Sci.nanotech] Error in Allis and Drexler paper
Toby Kelsey <toby_kelsey@xxxxxxxxxxxx> writes: > I have just read
"Design and Analysis of a Molecular Tool for Carbon > Transfer in
Mechanosynthesis" by Allis and Drexler >
(J. Comput. Theor. Nanosci. 2, 4555, 2005), available online at >
<http://e-drexler.com/d/05/00/DC10C-mechanosynthesis.pdf>, and it
> seem to me that there is a basic error in their calculations.
In > section 4.4 they compute the probability[...] I asked Eric
Drexler for comment. He wrote me this (I think he did not
understand who had made the original comment): From: K.Eric
Drexler Subject: Re: Error in Allis and Drexler paper To: "Perry
E. Metzger" Cc: Damian Gregory Allis Date: Tue, 31 Jan 2006
11:03:23 -0800 Dear Perry,
Thank you for reading and examining "Design and Analysis of a
Molecular Tool for Carbon Transfer in Mechanosynthesis". If I am
not mistaken, the model of configurational entropy effects
suggested by your note would, if taken literally, indicate an
error rate of 100% for all placement operations. Also, any error
rate that operated on a "per vibration" basis would approach 100%
in the limit of slow placement motions. These results cannot be
right.
Regarding more realistic estimates of placement errors, please
examine Section 6.3, "Placement Errors" (pp 130 - 134) of
Nanosystems, which addresses this issue. The approximations
presented there of course take account of configurational entropy;
as you suggest, omitting this would be a very elementary mistake.
Would you please post this note where it will be seen by readers
of your original comment?
With best wishes,
-- Eric
.
