Automorphisms of Z–subshifts of Finite Type
نویسندگان
چکیده
Let (Σ, σ) be a Zd subshift of finite type. Under a strong irreducibility condition (strong specification), we show that Aut(Σ) contains any finite group. For Zd–subshifts of finite type without strong specification, examples show that topological mixing is not sufficient to give any finite group in the automorphism group in general: in particular, End(Σ) may be an abelian semigroup. For an example of a topologically mixing Z2–subshift of finite type, the endomorphism semigroup and automorphism group are computed explicitly. This subshift has periodic–point permutations that do not extend to automorphisms.
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