2 citations · 2 across the 1 of their papers we have counts for
6 papers
Positive enumerable functors
Barbara Csima, Dino Rossegger, Zhi Ying "Daniel" Yu
We study reductions well suited to compare structures and classes of structures with respect to properties based on enumeration reducibility. We introduce the notion of a positive…
Which Classes of Structures Are Both Pseudo-elementary and Definable by an Infinitary Sentence?
Will Boney, Barbara F. Csima, Nancy A. Day +1
When classes of structures are not first-order definable, we might still try to find a nice description. There are two common ways for doing this. One is to expand the language, le…
Optimal bounds for single-source Kolmogorov extractors
Laurent Bienvenu, Barbara F. Csima, Matthew Harrison-Trainor
The rate of randomness (or dimension) of a string is the ratio where is the Kolmogorov complexity of . While it is known that a single computable transform…
The reverse mathematics of Hindman's theorem for sums of exactly two elements
Barbara F. Csima, Damir D. Dzhafarov, Denis R. Hirschfeldt +3
Hindman's Theorem (HT) states that for every coloring of with finitely many colors, there is an infinite set such that all nonempty sums of dist…
Degrees of Categoricity Above Limit Ordinals
Barbara F. Csima, Michael Deveau, Matthew Harrison-Trainor +1
A computable structure has degree of categoricity if is exactly the degree of difficulty of computing isomorphisms between isomorphic comput…
Degrees of categoricity on a cone
Barbara Csima, Matthew Harrison-Trainor
We investigate the complexity of isomorphisms of computable structures on cones in the Turing degrees. We show that, on a cone, every structure has a strong degree of categoricity,…