Applied Categorical Structures

, Volume 12, Issue 5–6, pp 537–576 | Cite as

Categorical and Combinatorial Aspects of Descent Theory

  • Ross Street


There is a construction which lies at the heart of descent theory. The combinatorial aspects of this paper concern the description of the construction in all dimensions. The description is achieved precisely for strict n-categories and outlined for weak n-categories. The categorical aspects concern the development of descent theory in low dimensions in order to provide a template for a theory in all dimensions. The theory involves non-abelian cohomology, stacks, torsors, homotopy, and higher-dimensional categories. Many of the ideas are scattered through the literature or are folklore; a few are new.

n-category weak n-category stack cohomology descent factorization system computad parity complex torsor 


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© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Ross Street
    • 1
  1. 1.Centre of Australian Category Theory, Mathematics DepartmentMacquarie UniversityNew South WalesAustralia. e-mail

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