Ieke Moerdijk

Ieke MoerdijkIzak (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 address: i.moerdijk at

Personal assistant: c.h.m.hens at

Some lecture notes

Under this link, you will find some notes of various courses on subjects in algebraic topology taught earlier at Utrecht and in Nijmegen.

Book on dendroidal sets and spaces

Under the following link you will find a preliminary version of the first part(s) of my book with Gijs Heuts entitled "Trees in Algebra and Topology: An introduction to dendroidal homotopy theory".

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In addition, here are links to some unpublished papers, or papers which are otherwise hard to find:

Some other material

Some other activities

Workshop on infinity operads, The Netherlands

·  2018, 11 to 14 June, website.

Higher Geometric Structures along the Lower Rhine, The Netherlands

·  2017, 19 and 20 October, edition X.

·  2019, 13 and 14 June, edition XIII.


KAN lectures