Homology, Homotopy and Applications
Volume 1 (1999)
Groupoids and crossed objects in algebraic topology
Pages: 1 – 78
This is an introductory survey of the passage from groups to groupoids and their higher dimensional versions, with most emphasis on calculations with crossed modules and the construction and use of homotopy double groupoids.
homotopy theory, groupoids, multiple groupoids, crossed modules, homotopy 2-types, crossed complexes, higher dimensional algebra
2010 Mathematics Subject Classification
01A60, 18Dxx, 18G55, 20Lxx, 55-02, 55-03, 55Q05