3 papers
math.CT2004
Covering groupoids
Zhi-Ming Luo
Topos properties of the category of covering groupoids over a fixed groupoid are discussed. A classification result for connected covering groupoids over a fixed groupoid analogous…
math.AT2004
Homotopy theory of presheaves of simplicial groupoids
Zhi-Ming Luo
We show that the category of presheaves of simplicial groupoids on a site is a right proper simplicial model category. We define -torsor of presheaf of 2-groupoids…
math.AT2003
Closed Model Categories for Presheaves of Simplicial Groupoids and Presheaves of 2-Groupoids
Zhi-Ming Luo, Peter Bubenik, Peter T. Kim
It is shown that the category of presheaves of simplicial groupoids and the category of presheaves of 2-groupoids have Quillen closed model structures. Furthermore, their homotopy…