Universality and Complexity in Cellular Automata

S. Wolfram / Universality and complexity in cellular automata
then this dependence may be arbitrarily complex,
and the behaviour of the system can be found by
1,10 procedure significantly simpler than direct sim~Iation. No meaningful prediction is therefore
possible for such systems.
Acknowledgements
I am grateful to many people for discussions,
including C. Bennett, J. Crutchfield, D. Friedan, P.
Gacz, E. Jen, D. Lind, O. Martin, A. Odlyzko, N .
Packard, S2. Shenker, W. Thurston, T. Toffoli and
S. Willson. I am particularly grateful to J. Milnor
for extensive discussions and suggestions.
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