Margarete Ketelsen
Max-Planck-Institute for Mathematics
Vivatsgasse 7
53111 Bonn
Office: 308
Email: lastname@mpim-bonn.mpg.de
Previously, I completed my PhD at the University of Münster, where I was a member of the Cluster of Excellence Mathematics Münster: Dynamics - Geometry - Structure. My PhD thesis Understanding the model theory of henselian valued fields by parts was supervised by Prof. Dr. Franziska Jahnke.
I am interested in the model theory of valued fields, in particular: tame valued fields, perfectoid fields & tilting and (relative) quantifier elimination, also definability of valuations.
Preprints
- NEW! AKE principles in roughly deeply ramified henselian valued fields (with Franziska Jahnke and Floris Vermeulen)
- Definability via the tilting correspondence (with Gessica Alecci, Ihsane Hadeg, Franziska Jahnke and Isabella Negrini), results from our WINE5 project
- Composition Ax-Kochen/Ershov principles and tame fields of mixed characteristic (with an appendix by Philip Dittmann)
- Definable Henselian valuations in positive residue characteristic (with Simone Ramello and Piotr Szewczyk), to appear in J. Symb. Log.
Talks
Notes and Slides from past talks
- Understanding the model theory of henselian valued fields by parts, 22 September 2026, Colloquium Logicum, Universität Würzburg (invited speaker for the PhD Colloquium). notes
- Model-theoretic tilting, 4 August 2025, ddg40 : Structures algébriques et ordonnées, Banyuls-sur-Mer (France). slides
- Definable Henselian valuations in positive residue characteristic (about joint work with Simone Ramello and Piotr Szewczyk),
- 13 March 2024, Young Women in Model Theory and Applications, Hausdorff Center for Mathematics in Bonn. notes
- 7 February 2024, LLAMA Seminar, ILLC Amsterdam. notes
- 9 November 2023, GRK 2240, Düsseldorf. notes
- 4 October 2023, PhDs in Logic, Granada. slides
- A proof of Greenberg's Theorem using ultrapowers, 19 August 2021, ALGAR 2021 Summer School, Antwerp. slides
Theses
- PhD thesis: Understanding the model theory of henselian valued fields by parts, Universität Münster, 2026. (advisor: Prof. Dr. Franziska Jahnke)
- Master's thesis: Quasi-finite axiomatizability in the class of finitely generated rings, Technische Universität Dresden, September 2022. (advisors: Prof. Dr. Arno Fehm, Dr. Philip Dittmann)
- Bachelor's thesis (in German): Polynomgleichungen über henselschen Bewertungsringen (Polynomial equations over Henselian valuation rings), Technische Universität Dresden, July 2020. (advisors: Prof. Dr. Arno Fehm, Dr. Philip Dittmann)