Affiliation:
1. Mathematics Department, Yale University, CT, USA. j.barnes@yale.edu
Abstract
The decidability of the two quantifier theory of the hyperarithmetic degrees below Kleene’s O in the language of uppersemilattices with least and greatest element is established. This requires a new kind of initial segment result and a new extension of embeddings result both in the hyperarithmetic setting.
Subject
Artificial Intelligence,Computational Theory and Mathematics,Computer Science Applications,Theoretical Computer Science
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