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> On Sat, 27 Jun 1998 Michael Nielsen <mnielsen@tangelo.phys.unm.edu> Wrote:
>
> >Our solid state computing devices have error rates in the
10^{-18}
> >range, while single particle systems are lucky to get down to
10^{-2}.
>
>
> I don't know what you mean by "single particle systems", or where you got
> that figure.
10^{-18} is an estimate from a condensed matter physicist and
colleague at IBM. 10^{-2} is from scores of research talks by people
working on this kind of thing, in many different architectures. Most of
the talks have been oriented towards quantum computing, but a good
number have been oriented towards conventional computing as well.
10^{-2} may be slightly pessimistic; 10^{-3} is not, in my opinion, and
10^{-4} is wildly optimistic.
I'm not sure what the problem is with "single particle
systems". Admittedly, they are not the only subject of
discussion here, but they provide a convenient reference point
at one end of the size spectrum.
> >Could you please send me a reference to Merkle's work on this?
>
>
> Drexler discuses Merkle's work on pages 82-85 in Nanosystems, he also lists
> many other articles by Merkle and others in the field of Reversible
Computers.
I'll have a look. Thanks also to Anders Sandberg for the link to Merkle's
page. In the "interesting facts" file, I'll mention that while a 1973
paper by Bennett in the IBM Journal of Research and Development is
usually credited as the discovery of reversible computation,
the following paper:
@article{Lecerf63a,
author={Y.~Lecerf},
title={Machines de {Turing} r\'eversibles},
journal={Comptes Rendus},
volume={257},
pages={2597-2600},
year={1963}}
appears to be where reversible computing first appeard. I say "appears"
because I don't read French; I have been told that it does contain an
architecture for a universal, reversible Turing machine. The Bennett
article is
@article{Bennett73a,
author={C.~H.~Bennett},
title={Logical reversibility of computation},
journal={IBM Journal of Research and Development},
volume={17},
number={6},
pages={525--32},
year={1973}}
Michael Nielsen
http://wwwcas.phys.unm.edu/~mnielsen/index.html