Abstract. We prove a version of the associated sheaf functor theorem in Algebraic Set Theory. The proof is established working within a Heyting pretopos equipped with a system of s...
The principal result of this paper answers a long-standing question in the model theory of arithmetic [KS, Question 7] by showing that there exists an uncountable arithmetically cl...
Abstract. We study the relationship between algebraic structures and their inverse semigroups of partial automorphisms. We consider a variety of classes of natural structures inclu...
Jennifer Chubb, Valentina S. Harizanov, Andrei S. ...
There is a perfect thin 0 1 class whose upward closure in the Turing degrees has full measure (and indeed contains every 2-random degree.) Thus, in the Muchnik lattice of 0 1 class...
Consider the following restriction of the polymorphically typed lambda calculus ("System F"). All quantifications are parameter free. In other words, in every universal ...
Building on previous work by Coquand and Spiwack [8] we construct a strict domaintheoretic model for the untyped -calculus with pattern matching and term rewriting which has the p...