I am a fourth year PhD student at the Mathematical Institute of the University of Bonn under the supervision of Carl-Friedrich Bödigheimer, in the area of algebraic topology. I am funded by the Max Planck Institute for Mathematics in Bonn and am a member of the International Max Planck research school (IMPRS) on moduli spaces.

• My ORCID record,
• Professional homepage at the University of Bonn,
• Curriculum Vitæ,
• Bonn Topology Group,
• Max Planck Institute for Mathematics.

Research interests

My PhD project deals with coloured topological operads and their algebras, configuration spaces, and the phenomenon of homological stability, as well as mapping class groups, moduli spaces of Riemann surfaces and their homology.

More recently, I have been studying low-dimensional equivariant and parametrised cobordism categories and their homotopy type.

My co-authors are Andrea Bianchi from the University of Copenhagen and Jens Reinhold from the University of Münster.

Teaching

In the summer term 2020, I co-organised a graduate seminar on Operads in Algebra and Topology together with Andrea Bianchi. Moreover, I have been tutor for the following topology lectures:

summer 2021	Algebraic Topology 2	Carl-Friedrich Bödigheimer
winter 2020/21	Algebraic Topology 1	Carl-Friedrich Bödigheimer
summer 2020	Algebraic Topology 2	Christoph Winges
winter 2019/20	Algebraic Topology 1	Wolfgang Lück
summer 2019	Topology 2	Daniel Kasprowski
winter 2018/19	Topology 1	Wolfgang Lück
summer 2018	Geometrie und Topologie	Wolfgang Lück

Preprints

• Parametrised moduli spaces of surfaces as infinite loop spaces

  12/05/2021, arXiv:2105.05772, with Andrea Bianchi and Jens Reinhold

  We study the E₂-algebra \(\Lambda\mathfrak{M}\) consisting of free loop spaces of moduli spaces of Riemann surfaces with one parametrised boundary component, and compute the homotopy type of the group completion \(\Omega B\Lambda\mathfrak{M}\): it is the product of \(\Omega^\infty\mathbf{MTSO}(2)\) with a certain free \(\Omega^\infty\)-space depending on the family of all boundary-irreducible mapping classes in all mapping class groups \(\Gamma_{g,n}\) with \(g\geqslant 0\) and \(n\geqslant 1\).

• Configuration spaces of clusters as E_d-algebras

  06/04/2021, arXiv:2104.02729

  It is a classical result that configuration spaces of labelled particles in \(\mathbb{R}^d\) are free algebras over the little \(d\)-cubes operad, and their d-fold bar construction is equivalent to the \(d\)-fold suspension of the labelling space. The aim of this paper is to study a variation of these spaces, namely the configuration space of labelled clusters of points in \(\mathbb{R}^d\). This configuration space is again an E_d-algebra, but in general not a free one. We give geometric models for their iterated bar construction in two different ways: one uses an additional verticality constraint, and the other one uses a description of these clustered configuration spaces as cellular E₁-algebras. In the last section, we show a stable splitting result and present some applications.

• Vertical configuration spaces and their homology

  22/03/2021, arXiv:2103.12137, with Andrea Bianchi

  We introduce ordered and unordered configuration spaces of ‘clusters’ of points in an Euclidean space \(\mathbb{R}^d\), where points in each cluster have to satisfy a ‘verticality’ condition, depending on a decomposition \(d=p+q\). We compute the homology in the ordered case and prove homological stability in the unordered case.

• Moduli spaces of Riemann surfaces and symmetric products: A combinatorial description of the Mumford–Miller–Morita classes

  25/09/2018, PDF (911 kiB)

  This is my master’s thesis which was finished in the summer term 2018. Its main result is a Poincaré–Lefschetz correspondene between the Mumford–Miller–Morita classes in the cohomology of moduli spaces and certain simplicial subcomplexes of Bödigheimer’s model of parallel slit domains.

Selected talks

• Homotopy coherent multiplications and loop spaces

  05/11/2020, PDF (1.1 MiB)

  These are the notes of a talk I gave in the winter term 2020/21 in our IMPRS seminar at the MPI. They tell a classical story about H-spaces, loop spaces, and May’s recognition principle.

• An introduction to model categories

  10/06/2020, PDF (1.3 MiB)

  In summer 2020, the first ‘corona term’, I gave an introductory talk on model categories in our IMPRS seminar. It was the first in a series of four talks and essentially covers the first chapter of Hovey’s book on the topic.