Ieke Moerdijk


iekeIzak (Ieke) Moerdijk studied Mathematics, Philosophy and General Linguistics at the University of Amsterdam. He received his PhD in Mathematics from the same institution in 1985, with the distinction Cum Laude. Subsequently he worked at the University of Chicago and at the University of Cambridge, before joining the Mathematics Department of Utrecht University in 1988. In 2011, he moved to Radboud University in Nijmegen. In 2016 he moved back to the University of Utrecht.


Moerdijk was awarded a Huygens Fellowship from NWO in 1986 and a PIONIER grant, again from NWO, in 1995. He was elected member of the KNAW (Royal Academy of Arts and Sciences) in 2006, and of the Academia Europaea in 2014. In 2011 Moerdijk received the Descartes-Huygens prize from the Académie des Sciences, and in 2012 the Spinoza Prize from NWO. He held visiting positions at Cambridge (St John's College), Montreal (McGill University), Sydney (University) and Aarhus, among others.


Moerdijk's research interests include algebraic and differential topology, and applications of topological structures in mathematical logic. He is the coauthor of several well-known books, including "Sheaves in Geometry and Logic" with S. Mac Lane (Springer Verlag,1992, 1994), and "Introduction to Foliations and Lie Groupoids" with J. Mrcun (Cambridge UP, 2003). Currently, his main focus is on developing the theory of dendroidal sets.




Email:     i.moerdijk at

                 personal assistant c.lemette at



Preprints and Publications

Moerdijk's preprints can be found here, while most of his publications are here.


In addition, here are links to some unpublished papers, or papers which are otherwise hard to find:

* Cyclic sets as a classifying Topos

* A paper on the weak homotopy type of etale groupoids

* A paper on the six operations of Grothendieck for etale groupoids

* Lecture at ECM 2000

* Bisimplicial sets and the Group-Completion Theorem




Some other material

Obituary of D(a)an Kan (in Dutch), published in the Levensberichten (obituaries) 2014 of the Dutch Royal Academy of Arts and Sciences.

Lecture presented at the Académie des Sciences on the occasion of the Descartes-Huygens Prize (2012).

Lecture on the occasion of the Dies Natalis in 2008 of Utrecht University  (in Dutch).



Some other activities

KAN lectures  

  Abstract 2016 Graeme Segal

European Autumn School in Topology, September 19-23, 2016

Topology Day, September 27th, 2016




Moerdijk is or was editor of the following journals and book series:


Journal of Generalized Lie Theory and Applications (2006-2016)

The Journal of Pure and Applied Algebra (2002-2007)

The Annals of Pure and Applied Logic (1993-2014)

Theory and Applications of Categories

North Western European Journal of Mathematics, a new journal to which submissions are encouraged.

Higher Structures, another new journal.

North Holland Mathematical Library (Elsevier)

Algebra and Applications (Springer)