3 papers
math.CT2025
Hopf formulae for cocommutative Hopf algebras
Marino Gran, Andrea Sciandra
The adjunction between coalgebras and Hopf algebras, first described by Takeuchi, allows one to prove that the semi-abelian category of cocommutative Hopf algebras has enough $\mat…
math.RA2024
Hopf braces and semi-abelian categories
Marino Gran, Andrea Sciandra
Hopf braces have been introduced as a Hopf-theoretic generalization of skew braces. Under the assumption of cocommutativity, these algebraic structures are equivalent to matched pa…
math.CT2024
Double groupoids and -groupoids in regular Mal'tsev categories
Nadja Egner, Marino Gran
We prove that the category 2- of internal -groupoids is a Birkhoff subcategory of the category of double groupoids…