Minimal bounds and members of effectively closed sets

2018/06/25 by Ahmet Çevik, Çevik, Ahmet
Computer Science · #Computability, Logic, AI Algorithms #semigroups and automata theory #Cellular Automata and Applications

paper · pdf · doi:10.48550/arxiv.1806.09368

Abstract

We show that there exists a non-empty special Π⁰₁ class in which no member is a minimal cover for any set, hence prove that degrees of minimal covers cannot be a basis for Π⁰₁ classes.

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