Equicontinuous factors of one dimensional cellular automata

Abstract

We are interested in topological and ergodic properties of one dimensional cellular automata. We show that an ergodic cellular automaton cannot have irrational eigenvalues. We show that any cellular automaton with an equicontinuous factor has also as a factor an equicontinuous cellular automaton. We show also that a cellular automaton with almost equicontinuous points according to Gilman's classification has an equicontinuous measurable factor which is a cellular automaton. 2000 Mathematics Subject Classification.: 37B15, 54H20, 37A30. Key words and phrases. Cellular Automata, Dynamical systems, equicontinuous factor.