Junior Professor Dr. Franziska Jahnke

© Astrid Pawlowitzki

Franziska Jahnke is a junior professor at the Mathematical Institute and the Institute for Mathematical Logic and Foundational Research, her area is the model theory of fields. Her work combines mathematical logic with applications in algebra.

A large part of her work deals with Shelah's conjecture about NIP fields. Studying definable sets in valued fields forms a basis for this work. In recent years, the first small steps towards successfully deciphering the Shelah conjecture have been achieved, partly thanks to her work.


What are the most beautiful aspects about being a mathematician for you?

I love to delve into the world of pure mathematics and to leave everything else behind. Once I have started to develop insights into a problem, it often takes a firm hold of me - in this stage of deep concentration, I can forget almost anything else around me.

However, it is not just the intellectual challenge of solving problems that keeps me interested but also the secondary virtues of being a researcher: I also very much enjoy interacting with the international model theory community, be it at conferences or via video calls. In particular, I really like exchanging ideas with my colleagues both here in Münster and far away, many of whom have become my close friends over time.


Franziska Jahnke, born in 1985, studied mathematics at the University of Freiburg and received her doctorate from the University of Oxford in 2013. She has been conducting research at the University of Münster since then, first as a research assistant and, since 2017, as a Mathrix junior professor. Since 2019, the mother of two children has been a scholarship holder of the Daimler and Benz Foundation. From January 2022, she will be accepted into the "Junges Kolleg" of the North Rhine-Westphalian Academy of Sciences and Arts.


Looking back, what were the most important moments in your career?

For many different problems that I solved in the past few years, I still remember the precise moment when I had the key idea. For my PhD, the main idea came to me when hiking in the alps, for my current work on NIP fields, the two biggest breakthroughs began with insights I had while on a playground and at the stables. Even though I work a lot attempting to organize my thoughts with pen and paper, the main steps forward always seem to happen in the great outdoors.

However, having good ideas on how to drive one's research forward (and persistence when nothing seems to move forward for a long while) is of course not everything necessary for being successful! Also very important for me were the chances I received during my career, from the offers for a PhD scholarship in Oxford and a postdoc position in Münster to the Mathrix position that I hold now, as well as many invitations to present my work at conferences all over the world.


published: May 2020

Selected publications:

  • Franziska Jahnke and Jochen Koenigsmann: Uniformly defining p-henselian valuations. Annals of Pure and Applied Logic, Vol. 166 (2015), pp. 741-754, doi:10.1016/j.apal.2015.03.003.
  • Yatir Halevi, Assaf Hasson and Franziska Jahnke: Definable V-topologies, Henselianity and NIP. Journal of Mathematical Logic, Vol. 20, No. 02, 2050008 (2020), doi:10.1142/S0219061320500087.
  • Sylvy Anscombe and Franziska Jahnke: The model theory of Cohen rings. Accepted for publication in Confluentes Mathematici, 2019, arXiv:1904.08297.