Classifying spaces for toposes with enough points

  • Ieke Moerdijk


This paper provides an introduction to and a survey of recent work with C. Butz. The central construction is that of a “classifying space” for any Grothendieck topos with enough points. It is proved that this space has the same cohomology and homotopy groups as the topos. The construction also has applications in mathematical logic, where it yields new topological completeness theorems.


Topological Space Topological Model Completeness Theorem Faithful Functor Topological Groupoid 
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Copyright information

© Birkhäuser-Verlag 1998

Authors and Affiliations

  • Ieke Moerdijk
    • 1
  1. 1.Universiteit UtrechtUtrechtThe Netherlands

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