Every Low 2 Boolean Algebra Has a Recursive Copy
نویسنده
چکیده
The degree of a structure si is the Turing degree of its open diagram £»(j/) , coded as a subset of a>. Implicit in the definition is a particular presentation of the structure; the degree is not an isomorphism invariant. We prove that if a Boolean algebra si has a copy of low 2 degree, then there is a recursive Boolean algebra 33 which is isomorphic to si . This builds on work of Downey and Jockusch, who proved the analogous result starting with a low i Boolean algebra.
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