4 papers
Profinite approach to S-adic shift spaces I: Saturating directive sequences
Jorge Almeida, Alfredo Costa, Herman Goulet-Ouellet
This paper is the first in a series of three, about (relatively)free profinite semigroups and S-adic representations of minimal shift spaces. We associate to each primitive S-adic…
Open multiplication in relatively free profinite semigroupoids
Jorge Almeida, Alfredo Costa, Herman Goulet-Ouellet
The purpose of this paper is to extend some useful results, such as the multiplication being open, previously known for suitable finitely generated relatively free profinite semigr…
Eilenberg correspondence for Stone recognition
Jorge Almeida, OndÅej KlÃma
We develop and explore the idea of recognition of languages (in the general sense of subsets of topological algebras) as preimages of clopen sets under continuous homomorphisms int…
Pseudovarieties of semigroups
Jorge Almeida
The most developed aspect of the theory of finite semigroups is their classification in pseudovarieties. The main motivation for investigating such entities comes from their connec…