English

The Bicategory of Lie Groupoids within Diffeological Groupoids

Differential Geometry 2026-01-29 v4 Category Theory

Abstract

We consider the localisation of the 2-category of diffeological groupoids at weak equivalences from the perspective of anafunctors, and with this language, prove that the localisation of the 2-category of Lie groupoids is an essentially full sub-bicategory of that of diffeological groupoids. In particular, we solve the open problem affirmatively of whether two Lie groupoids that are diffeologically Morita equivalent are Morita equivalent in the usual Lie sense.

Keywords

Cite

@article{arxiv.2206.12730,
  title  = {The Bicategory of Lie Groupoids within Diffeological Groupoids},
  author = {Jordan Watts},
  journal= {arXiv preprint arXiv:2206.12730},
  year   = {2026}
}

Comments

30 pages; v4 has a new subsection on foliations and minor edits; v3 is a condensed version of v2, focusing on anafunctors and bibundles and new results, but without the bicategorical detail; v2 (84 pages) is essentially the same as v1 with some small modifications to the introduction and typographical corrections. To appear in the Journal of Geometry & Physics