Generating Sets for the Recursively Enumerable Turing Degrees
نویسندگان
چکیده
One of the recurrent themes in the area of the recursively enumerable (r.e.) degrees has been the study of the meet operator. While, trivially, the partial ordering of the r.e. degrees is an upper semi-lattice, i.e., the join ∗Lempp was partially supported by NSF grant DMS-0140120 and a Mercator Guest Professorship of the Deutsche Forschungsgemeinschaft. †Slaman was partially supported by the Alexander von Humboldt Foundation and by National Science Foundation Grant DMS-9988644.
منابع مشابه
CDMTCS Research Report Series Difference Splittings of Recursively Enumerable Sets
We study here the degree-theoretic structure of set-theoretical splittings of recursively enumerable (r.e.) sets into differences of r.e. sets. As a corollary we deduce that the ordering of wtt–degrees of unsolvability of differences of r.e. sets is not a distributive semilattice and is not elementarily equivalent to the ordering of r.e. wtt–degrees of unsolvability.
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