Meetings Organized


Topology Workshop in Oberwolfach

July 1-7, 2018,

joint with Mark Behrens, Ruth Charney and Michael Weiss.


Arbeitstagung on "Physical Mathematics" in honor of Yuri Manin,

Conference at MPIM, June 19-23, 2017.

Joint with Christian Blohmann, Mikhail Kapranov and Bruno Vallette.


4-Manifolds and knot concordance,

Max-Planck Institute for Mathematics in Bonn, October 17-21, 2016,

joint with the low-dimensional HIM gang, see website.


Topology Workshop in Oberwolfach

July 17-23, 2016,

joint with Mark Behrens, Natelie Wahl and Michael Weiss.


Factorization Algebras and Functorial Field Theories

Workshop in Oberwolfach, May 8-14, 2016,

joint with Owen Gwilliam, Stephan Stolz and Mahmoud Zeinalian.


Higher structures in Geometry and Physics 2016, a thematic program

at the Max-Planck Institute for Mathematics in Bonn, January - March, 2016,

Michael Batanin, Ralph Kaufmann and Martin Markl.

(Scientific advisory board joint with Yuri Manin)


Higher structures in Geometry and Physics 2015, a workshop

at the Max-Planck Institute for Mathematics in Bonn, Oct.12-16, 2015,

joint with Anton Alekseev, Christian Blohmann, Chris Schommer-Pries and Chenchang Zhu.


Homotopy theory, manifolds and field theories,

Trimester program at the Hausdorff Institute for Mathematics in Bonn, May 4 - August 21, 2015,

joint with Soren Galatius, Haynes Miller and Stefan Schwede.


Special activities during the trimester:

          • May 4-8: Introductory School for graduate students and postdocs with lecture series

           by D. Ayala, O. Randal-Williams, S. Schwede, P. Teichner


          • June 1-19: Felix Klein Lectures by Charles Rezk


          • June 15-19: Workshop at the Max Planck Institute for Mathematics

          • August 17-21: Geometry & Topology Conference


Geometric quantization and topological recursion

November 24-28, 2014 at the Max Planck Institute for Mathematics, Bonn

joint with Gaetan Borot and Don Zagier.


Topology Workshop in Oberwolfach

September 14-20, 2014,

joint with Thomas Schick, Natelie Wahl and Michael Weiss.


20th NRW Topology Meeting, Max-Planck Institute for Mathematics in Bonn, November 8 - 9, 2013, joint with Wolfgang Lück and Stefan Schwede.


Network Meeting in String Geometry, Max-Planck Institute for Mathematics in Bonn, October 7 -11, 2013, joint with Bas Janssens and Thomas Nikolaus.

Includes a Minicourse on Dendroidal Topology by Ieke Moerdijk.


Arbeitstagung, dedicated to the memory of Friedrich Hirzebruch

Bonn, May 22-28, 2013,

joint with Werner Ballmann, Gerd Faltings and Don Zagier.


4-Manifolds and their combinatorial invariants, a special semester at the Max-Planck Institute for Mathematics in Bonn, January - June, 2013,

joint with Michael Freedman and Matthias Kreck.

Videos of Freedman’s Lectures

Videos of other Lectures


Topological aspects of quantum field theory, Workshop at the Institute of Mathematical Sciences in Singapore, Jan. 14-18, 2013, joint with Fei Han.