S. A. Terwijn
Published 2019-10-21Version 1
We prove a number of elementary facts about computability in partial combinatory algebras (pca's). We disprove a suggestion made by Kreisel about using Friedberg numberings to construct extensional pca's. We then discuss separability and elements without total extensions. We relate this to Ershov's notion of precompleteness, and we show that precomplete numberings are not 1-1 in general.
Sofic profiles of $S(ω)$ and computability
Computability for the absolute Galois group of $\mathbb{Q}$
On the computability of ordered fields
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