3 papers
math.CT2026
Observations on the variety of equationally linear Heyting semilattices
Xabier García-Martínez, James R. A. Gray, Michael A. Hoefnagel +2
In previous work, we analysed a number of categorical properties, of interest in the context of Janelidze-Márki-Tholen semi-abelian categories, for the variety of…
math.CT2026
On the zero-classes of monoid semi-congruences
M. Hoefnagel, N. Martins-Ferreira, M. Sobral
This paper studies the zero-classes of monoid semi-congruences, understood as internal reflexive relations on a monoid. Classical examples include normal submonoids, which arise as…
math.CT2025
Categorical-algebraic aspects of Heyting semilattices
Xabier García-Martínez, James R. A. Gray, Michael A. Hoefnagel +2
This article gives an overview of some key categorical-algebraic properties of the variety of Heyting semilattices, with the aim of correcting a misconception in the literature. We…