activity
20152025
most citedDifference-restriction algebras of partial functions: axiomatisations and representations

5 citations · 13 across the 11 of their papers we have counts for

collaborators

12 papers

math.LO2025

Difference-restriction algebras with operators

Célia Borlido, Ganna Kudryavtseva, Brett McLean

We exhibit an adjunction between a category of abstract algebras of partial functions that we call difference-restriction algebras and a category of Hausdorff étale spaces. Differe…

math.CT2023

Filtral pretoposes and compact Hausdorff locales

Célia Borlido, Panagis Karazeris, Luca Reggio +1

The category of compact Hausdorff locales is a pretopos which is filtral, meaning that every object is covered by one whose subobject lattice is isomorphic to the lattice of filter…

math.GN2023

Pervin spaces and Frith frames: bitopological aspects and completion

Célia Borlido, Anna Laura Suarez

A Pervin space is a set equipped with a bounded sublattice of its powerset, while its pointfree version, called Frith frame, consists of a frame equipped with a generating bounded…

math.GN2022

A pointfree theory of Pervin spaces

Célia Borlido, Anna Laura Suarez

We lay down the foundations for a pointfree theory of Pervin spaces. A Pervin space is a set equipped with a bounded sublattice of its powerset, and it is known that these objects…

cs.LO2021

Substitution Principle and semidirect products

Célia Borlido, Mai Gehrke

In the classical theory of regular languages the concept of recognition by profinite monoids is an important tool. Beyond regularity, Boolean spaces with internal monoids (BiMs) we…

math.LO2020★ 3 cited

Difference-restriction algebras of partial functions with operators: discrete duality and completion

Célia Borlido, Brett McLean

We exhibit an adjunction between a category of abstract algebras of partial functions and a category of set quotients. The algebras are those atomic algebras representable as a col…

math.LO2020★ 5 cited

Difference-restriction algebras of partial functions: axiomatisations and representations

Célia Borlido, Brett McLean

We investigate the representation and complete representation classes for algebras of partial functions with the signature of relative complement and domain restriction. We provide…

math.GN2018★ 3 cited

Difference hierarchies and duality with an application to formal languages

Célia Borlido, Mai Gehrke, Andreas Krebs +1

The notion of a difference hierarchy, first introduced by Hausdorff, plays an important role in many areas of mathematics, logic and theoretical computer science such as descriptiv…

math.GN2018★ 1 cited

A note on powers of Boolean spaces with internal semigroups

Célia Borlido, Mai Gehrke

Boolean spaces with internal semigroups generalize profinite semigroups and are pertinent for the recognition of not-necessarily regular languages. Via recognition, the study of ex…

math.GR2015

Complete kappa-reducibility of pseudovarieties of the form DRH

Jorge Almeida, Célia Borlido

We denote by kappa the implicit signature that contains the multiplication and the (omega-1)-power. It is proved that for any completely kappa-reducible pseudovariety of groups H,…

math.GR2015★ 1 cited

The kappa-word problem over DRH

Célia Borlido

Let H be a pseudovariety of groups in which the kappa-word problem is decidable. Here, kappa denotes the canonical implicit signature, which consists of the multiplication and the…

math.GR2015

Some reducibility properties for pseudovarieties of the form DRH

Célia Borlido

Let H be a pseudovariety of groups and DRH be the pseudovariety containing all finite semigroups whose regular R-classes belong to H. We study the relationship between reducibility…