One thing this tells me is that there is not much room left at the
bottom, pace Feynman. That is to say, we are already reaching the
limits. IBM has made a single-atom transistor and a 12-atom magnetic
memory:
http://www.dailytech.com/Scientists+Cook+Up+1Atom+Transistor+12Atom+Magnetic+Storage/article24038.htm
Present day memories are about 1 million atoms per bit. I suppose they
might get down to 1,000 atoms, but that's only 3 orders of magnitude,
which is nothing compared to the improvements in storage we have seen
since Feynman gave his talk in 1959, "There is Plenty of Room at the
Bottom."
A hydrogen atom is 10E-10. I assume that is the smallest device we can
ever make. A neutrino is 10E-22, and there is nothing below that, all
the way down to the Planck length, 10E-35. It is not all that far down
to the bottom.
We might still improve computer storage by huge amounts using
3-dimensional storage.
In the distant future, perhaps supercomputers will be the size of small
planets after all, as predicted by Asimov. Imagine an MPP computer
thousands of kilometers across packed with circuits and memory bits each
the size of a few thousand atoms. Knowing people as I do, I suppose such
a thing will be used to develop weapons.
- Jed
