2 papers
math.LO2025
A non-computable c.e. closed subset of
Serikzhan Badaev, Nikolay Bazhenov, Sergey Goncharov +2
We prove that there exists a closed subset of that is not homeomorphic to any computably compact space. We show that the index set of c.e. subspaces of that…
math.LO2023
A note on the degree structure of primitive recursive m-reducibility
Birzhan Kalmurzayev, Nikolay Bazhenov, Alibek Iskakov
Let be the upper semilattice of degrees of computable sets with respect to primitive recursive -reducibility. We prove that the first-order theory of is he…