3 papers
math.QA2026
The Ring of Differential Operators on a Nodal Curve is not a Bialgebroid
Myriam Mahaman
In a previous article, we showed that local projectivity is a sufficient condition for the existence of a bialgebroid structure on the ring of differential operators on an affine v…
math.QA2024
The ring of differential operators on a monomial curve is a Hopf algebroid
Ulrich Krähmer, Myriam Mahaman
This article considers cuspidal curves whose coordinate rings are numerical semigroup algebras. Using a general result about descent of Hopf algebroid structures, their rings of di…
math.CT2021
Clones from comonoids
Ulrich Krähmer, Myriam Mahaman
The fact that the cocommutative comonoids in a symmetric monoidal category form the best possible approximation by a cartesian category is revisited when the original category is o…