The trace subshift of a cellular automaton is the subshift of all possible columns that may appear in a space-time diagram. In this paper we study conditions for a sofic subshift to be the trace of a cellular automaton.

We systematically investigate the e ect of blockage sites in a cellular automaton model for tra c ow. Di erent scheduling schemes for the blockage sites are considered. None of them returns a linear relationship between the fraction of \green" time and the throughput. We use this information for a fast implementation of a simulation of tra c in Dallas.

A one-dimensional cellular automaton with a probabilistic evolution rule can generate stochastic surface growth in (1 + 1) dimensions. Two such discrete models of surface growth are constructed from a probabilistic cellular automaton which is known to show a transition from a active phase to a absorbing phase at a critical probability associated with two particular components of the evolution r...

We study a classification of cellular automata based on the Turing degree of the orbits of the automaton. The difficulty of determining the membership of a cellular automaton in any one of these classes is characterized in the arithmetical hierarchy.