English

Groupoid G-spans and matrices over group rings

Category Theory 2026-03-24 v1

Abstract

When G is a finite abelian group, we define G-spans of groupoids and their associated matrices with entries in the group ring QG and show that composition of spans corresponds to multiplication of matrices.

Keywords

Cite

@article{arxiv.2603.20787,
  title  = {Groupoid G-spans and matrices over group rings},
  author = {Joachim Kock and Jesper M. Møller},
  journal= {arXiv preprint arXiv:2603.20787},
  year   = {2026}
}

Comments

27pp

R2 v1 2026-07-01T11:31:22.136Z