3 papers
math.LO2026
Infinite Belligerent Jump Inversion and Computable Scott Analysis
Uri Andrews, David Gonzalez, Hongyu Zhu
Scott analysis provides two fundamental tools for studying countable structures: Scott sentences, which characterize structures up to isomorphism, and back-and-forth relations, whi…
math.LO2025
The Borel complexity of the class of models of first-order theories
Uri Andrews, David Gonzalez, Steffen Lempp +2
We investigate the descriptive complexity of the set of models of first-order theories. Using classical results of Knight and Solovay, we give a sharp condition for complete theori…
math.LO2024
A jump operator on the Weihrauch degrees
Uri Andrews, Steffen Lempp, Alberto Marcone +2
A partial order admits a jump operator if there is a map that is strictly increasing and weakly monotone. Despite its name, the jump in the Weihrauch la…