38 citations · 49 across the 4 of their papers we have counts for
4 papers
A Categorification of Hall Algebras
Christopher Walker
In recent years, there has been great interest in the study of categorification, specifically as it applies to the theory of quantum groups. In this thesis, we would like to provid…
Hall Algebras as Hopf Objects
Christopher D. Walker
One problematic feature of Hall algebras is the fact that the standard multiplication and comultiplication maps do not satisfy the bialgebra compatibility condition in the underlyi…
Higher-Dimensional Algebra VII: Groupoidification
John C. Baez, Alexander E. Hoffnung, Christopher D. Walker
Groupoidification is a form of categorification in which vector spaces are replaced by groupoids, and linear operators are replaced by spans of groupoids. We introduce this idea wi…
Groupoidification Made Easy
John C. Baez, Alexander E. Hoffnung, Christopher D. Walker
Groupoidification is a form of categorification in which vector spaces are replaced by groupoids, and linear operators are replaced by spans of groupoids. We introduce this idea wi…