[extropy-chat] Re: An Error in Nanosystems!

Chris Phoenix cphoenix at CRNano.org
Wed Apr 7 14:50:37 UTC 2004

Hal Finney wrote:
> Stop the presses!  I've found a mistake in Drexler's magnum opus,
> Nanosystems, the book in which it is said that no one has ever found
> an error.
> "...Note the six-fold symmetry of the
> shaft structure and the fourteen-fold symmetry of the surrounding ring;
> this relatively prime combination..."

For the past few months, I've been saying "no significant error" rather 
than no error whatsoever.  I lost all faith in Drexler when I found a 
typo in Nanosystems: one of the subscripts is wrong in the text applying 
one of his formulas, in the last paragraph of p. 353.  The second k(s,p) 
should be k(s,g).  I ripped up my copy at once, and renewed my 
subscription to Scientific American.

Which is easier to believe: that Drexler is an idiot who doesn't know 
what "relatively prime" means, or that he was thinking faster than he 
was writing and meant to say that *one-half* of the bearing (3 vs 7) 
represented a relatively prime combination?  If the whole bearing were 
relatively prime, it would wobble as the region of alignment traveled 
around the axis.  If there are two opposing regions of alignment, it 
won't wobble--but that requires that the numbers be mutually divisible by 2.

Drexler has told me that chemists frequently look at his 2D projections 
of 3D molecular designs, see two carbon atoms superimposed with a total 
of six bond-lines coming out, and accuse him of designing hexavalent 
carbon!  I guess for some idiots, it is easier to believe that he's an 

BTW, do you have the hardcover Nanosystems?  My softcover version has a 
different caption: "Note the six-fold symmetry of the shaft and 
fourteen-fold symmetry of the surrounding ring; with a least common 
multiple of 42, this combination yields..."


Chris Phoenix                                  cphoenix at CRNano.org
Director of Research
Center for Responsible Nanotechnology          http://CRNano.org

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