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Mathematisches Institut
Endenicher Allee 60
53115 Bonn, Germany

Office: 3.023
Tel: +49 228 73 62239
eMail: f.hebestreit at
Office hours: by appointment

Fabian Hebestreit

I am a Post-Doc in the Topology group at the University of Bonn under the supervision of Wolfgang Lück.
During the summer 2020 I will be visiting Søren Galatius at the University of Copenhagen. During the summer 2018 I was at the Newton Institute in Cambridge, UK, as a participant of the program Homotopy harnessing higher structures and for the winter term 17/18 I was on leave from Bonn as a visiting professor in the Differential Geometry group at the University of Augsburg substituting for Wolfgang Steimle.
Here is a CV.

Furthermore, I am currently the organiser of the Bonn topology seminar and organised the workshop Automorphisms of Manifolds with Wolfgang.

Research Interests

Manifolds, mostly high dimensional! That is: Algebraic & Geometric Topology with a view towards Differential Geometry.
More specifically at the moment: Surgery theory and its applications to scalar curvature questions; cobordism categories and characteristic classes of manifold bundles; twisted bordism groups and parametrised homotopy theory

Publications and Preprints

Articles for Conference Proceedings

  • with I. Bokor, D. Crowley, S. Friedl, D. Kasprowski, M. Land & J. Nicholson: Connected sum decompositions of high-dimensional manifolds.
    arXiv: 1909.02628 (2019, submitted)
  • The Tate Diagonal (extended abstract).
    Oberwolfach Reports vol. 15, no. 1, Arbeitsgemeinschaft: Topological Cyclic Homology (2018), pp. 825 - 838.
  • Twisted Spin Cobordism (extended abstract).
    Oberwolfach Reports vol. 11, no. 3, Workshop: Analysis, Geometry and Topology of positive scalar curvature (2014), pp. 2013 - 2014.

In preparation

  • with M. Joachim: A factorisation of the twisted index map via parametrised homotopy theory.
  • with S. Stolz: Q_0-acyclic A(1)-modules and the cohomology of K(Z/2,2).
  • with M. Land & G. Laures: Multiplicative properties of Ranicki's signature square.
  • with M. Land & G. Laures: Infinite loop space structures on G/Top.
  • with N. Perlmutter: Stable stability in odd dimensions.
  • with B. Calmès, E. Dotto, Y. Harpaz, M. Land, K. Moi, D. Nardin, T. Nikolaus & W. Steimle: Real K-theory of stable infinity-categories.


This semester I will teach the course Introduction to higher Categories together with Christoph Winges.

Previously, I was the teaching assistent of Daniel Kasprowski for the lecture course Topology II, and gave the course Mathematik für Geowissenschaftler II (in german). I ran seminars on Characteristic classes and Real Divisionalgebras (in german); I taught the lecture course Algebraic topology (in german), together with the two seminars The space of positive scalar curvature metrics, and Representation theory of finite groups (in german) at the University of Augsburg; I was the teaching assistant of Saint Nikolaus for the lecture course Algebraic Topology II, and that of Jens Franke for the lecture courses Linear algebra I, II and Introduction to algebra. More information can be found on the courses' websites.