Spectra of Algebraic Fields and Subfields
نویسندگان
چکیده
An algebraic field extension of Q or Z/(p) may be regarded either as a structure in its own right, or as a subfield of its algebraic closure F (either Q or Z/(p)). We consider the Turing degree spectrum of F in both cases, as a structure and as a relation on F , and characterize the sets of Turing degrees that are realized as such spectra. The results show a connection between enumerability in the structure F and computability when F is seen as a subfield of F .
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