Displaying 21 – 40 of 126

Showing per page

Computable categoricity versus relative computable categoricity

Rodney G. Downey, Asher M. Kach, Steffen Lempp, Daniel D. Turetsky (2013)

Fundamenta Mathematicae

We study the notion of computable categoricity of computable structures, comparing it especially to the notion of relative computable categoricity and its relativizations. We show that every 1 decidable computably categorical structure is relatively Δ⁰₂ categorical. We study the complexity of various index sets associated with computable categoricity and relative computable categoricity. We also introduce and study a variation of relative computable categoricity, comparing it to both computable...

Dense pairs of o-minimal structures

Lou van den Dries (1998)

Fundamenta Mathematicae

The structure of definable sets and maps in dense elementary pairs of o-minimal expansions of ordered abelian groups is described. It turns out that a certain notion of "small definable set" plays a special role in this description.

Currently displaying 21 – 40 of 126