Search
Search Results
-
Categoricity Spectra of Computable Structures
The categoricity spectrum of a computable structure S is the set of all Turing degrees capable of computing isomorphisms among arbitrary computable...
-
Strong Degrees of Categoricity and Weak Density
AbstractIt is well-known that every c.e. Turing degree is the degree of categoricity of a rigid structure. In this work we study the possibility of...
-
On Decidable Categoricity for Almost Prime Models of the Signature of Graphs
AbstractWe study the degrees of decidable categoricity for almost prime models and their relationship with the degrees of the sets of complete...
-
The Degree of Decidable Categoricity of a Model with Infinite Solutions for Complete Formulas
We construct a decidable prime model in which the degree of a set of complete formulas is equal to 0 ' , infinitely many tuples of elements comply with...
-
Punctual Categoricity Relative to a Computable Oracle
AbstractWe are studying the punctual structures, i.e., the primitive recursive structures on the whole set of integers. The punctual categoricity...
-
On Decidable Categoricity and Almost Prime Models
AbstractThe complexity of isomorphisms for computable and decidable structures plays an important role in computable model theory. Goncharov [
26 ]... -
-
Degrees of bi-embeddable categoricity of equivalence structures
We study the algorithmic complexity of embeddings between bi-embeddable equivalence structures. We define the notions of computable bi-embeddable...
-
Computable Reducibility for Computable Linear Orders of Type ω
We study computable reducibility for computable isomorphic copies of the standard ordering of natural numbers. Following Andrews and Sorbi, we...
-
Bézout’s Theorem
Defining intersection multiplicity of two curves at a point. Two definitions are given: one is used to show geometric invariance of intersection...
-
The Complexity of Finding Supergraphs
We consider several variations of the following problem: fix a countable graph G. Is an input graph H a(n induced) subgraph of G? If yes, can we find...
-
Computable Linear Orders and the Ershov Hierarchy
AbstractIn this paper we provide corrections of an inaccuracy made in our previous paper. Namely, we correctly prove that there exists a computable...