4 papers
Primitive recursive categoricity spectra of functional structures
Nikolay Bazhenov, Heer Tern Koh, Keng Meng Ng
For the notion of degree of categoricity, we study an analogous notion for punctual structures. We show that such notions coincide for non--categorical injection struct…
Primitive recursive categoricity spectra
Nikolay Bazhenov, Heer Tern Koh, Keng Meng Ng
We study the primitive recursive analogue of computable categoricity spectra for various natural classes of structures. We show that these notions coincide for all relatively $Î_{…
Open Problems in Computability Theory and Descriptive Set Theory
George Barmpalias, Nikolay Bazhenov, Chi Tat Chong +11
These open problems were presented in the Problem Sessions held during the Tianyuan Workshop on Computability Theory and Descriptive Set Theory, June 16-20, 2025. The problems are…
Online and feasible presentability: from trees to modal algebras
Nikolay Bazhenov, Dariusz KalociÅski, MichaÅ WrocÅawski
We investigate whether every computable member of a given class of structures admits a fully primitive recursive (also known as punctual) or fully P-TIME copy. A class with this pr…