Since Edward Moore, finite automata theory has been inspired by physics, in
particular by quantum complementarity. We review automaton complementarity,
reversible automata and the connections to generalized urn models. Recent
developments in quantum information theory may have appropriate formalizations
in the automaton context.Comment: 12 pages, prepared for the Sixth International Conference on
Developments in Language Theory, Kyoto, Japan, September 18-21, 200
