Notes on commutation of limits and colimits
Category Theory
2015-05-06 v2 Group Theory
Abstract
We show that there are infinitely many distinct closed classes of colimits (in the sense of the Galois connection induced by commutation of limits and colimits in Set) which are intermediate between the class of pseudo-filtered colimits and that of all (small) colimits. On the other hand, if the corresponding class of limits contains either pullbacks or equalizers, then the class of colimits is contained in that of pseudo-filtered colimits.
Cite
@article{arxiv.1409.7860,
title = {Notes on commutation of limits and colimits},
author = {Marie Bjerrum and Peter Johnstone and Tom Leinster and William F. Sawin},
journal= {arXiv preprint arXiv:1409.7860},
year = {2015}
}
Comments
5 pages. Version 2: very minor edits