Categoricity Properties for Computable Algebraic Fields

نویسندگان

  • DENIS R. HIRSCHFELDT
  • KEN KRAMER
  • RUSSELL MILLER
  • ALEXANDRA SHLAPENTOKH
چکیده

We examine categoricity issues for computable algebraic fields. Such fields behave nicely for computable dimension: we show that they cannot have finite computable dimension greater than 1. However, they behave less nicely with regard to relative computable categoricity: we give a structural criterion for relative computable categoricity of these fields, and use it to construct a field that is computably categorical, but not relatively computably categorical. Finally, we show that computable categoricity for this class of fields is Π4-complete.

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تاریخ انتشار 2013