>
> It is difficult to imagine if a straightforward Turing approach would be able
> to capture the evolutionary process, which would seem to require random
> environmental inputs. Then again, there is an artificial life program by Tom
> Ray, introduced in 1990, called Tierra, which is used to simulate Darwinian
> evolution. I don't know if this program has been found to be a Universal Turing
> Machine.
>
> Happy Holidays,
> Fred
>
>
>
The Tierran computer language is capable of universal computation. (I
can't remember the exact reference, but it would probably be
cross-referenced on the Tierra web site). It is widely believed that
universal computation is necessary for "rich" evolvability, however I
remain sceptical on this issue.
As for randomness, Tierra uses pseudo random numbers in its
implementation. Depending on your point of view, this may make Tierran
organisms pseudo-alive. Of course, with an appropriate source of real
random numbers attached to your computer, this objection could be
readily taken care of, unlike with a strict Turing machine.
Cheers
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Dr. Russell Standish Director
High Performance Computing Support Unit,
University of NSW Phone 9385 6967
Sydney 2052 Fax 9385 6965
Australia R.Standish.domain.name.hidden
Room 2075, Red Centre
http://parallel.hpc.unsw.edu.au/rks
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Received on Wed Jan 05 2000 - 22:49:29 PST