> > Nobody has presented a self-replicating Life system. All Conway did was
> > produce a feasibility proof, so you know it *can* be done. Actually
> > designing such a system is still considered not yet possible.
>
> Really? I thought I've heard that the Universal Turing machine was
> actually designed, with streams of gliders serving as tape etc. But I
> may be wrong, in which case I'm glad you pointed it out. Do you have
> any references?
Reminds me of the kinds of talks Ralph Merkle does about nanotech. If
you can build a nand gate, and a wire, you can build a computer, and
therefore a UTM with a finite tape. I believe the logic elements and
wires are demonstrated for Life, ergo a UTM is possible. I recall a
remark that the grid needed to do this was huge, something like 10^9
cells on each side...
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| Hara Ra <harara@shamanics.com> |
| Box 8334 Santa Cruz, CA 95061 |
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so many stupid people, so few comets