English

Projective lines as groupoids with projection structure

Category Theory 2013-10-22 v1

Abstract

The coordinate projective line over a field is seen as a groupoid with a further `projection' structure. We investigate conversely to what extent such an, abstractly given, groupoid may be coordinatized by a suitable field constructed out of the geometry.

Keywords

Cite

@article{arxiv.1310.5357,
  title  = {Projective lines as groupoids with projection structure},
  author = {Anders Kock},
  journal= {arXiv preprint arXiv:1310.5357},
  year   = {2013}
}
R2 v1 2026-06-22T01:50:28.659Z