JProf. Dr. Franziska Jahnke
Mathematical Institute and
Institute for Mathematical
Logic and Foundational Research
Department of Mathematics and Computer Science
University of Münster
Einsteinstraße 62
48149 Münster (Germany)
Room: 801
Tel.: +49 251 83 32 764
e-mail: franziska.jahnke AT uni-muenster.de
Arithmetic and Model theory of fields, in particular perfectoid fields and finitely ramified henselian valued fields, arithmetic definability of valuations and connections to infinite combinatorics.
- Co-organizer of the conference Model theory of valued fields (CIRM, Luminy, 29.05.-02.06.2023)
- Invited speaker at the Joint Mathematics Meeting (ASL invited address), Boston, 2023.
- Talk Dividing lines in the model theory of fields Betty B. Seminar, November 2021, Paris
- Talk Decidability and definability in unramified henselian valued fields, Workshop on Trends in Pure and Applied Model Theory, Fields Institute, Toronto, 27.07.21
- Research Member at the MSRI Programm Decidability, Definability and Computability in Number Theory, August - December 2020
(my 5 minute talk)
- Co-organizer of the
Conference Model theory of valued fields and applications (Münster,
10.06.-14.06.2019)
- Franziska Jahnke:
Henselian Valuations and Absolute Galois Groups.
DPhil Thesis, 2013, Oxford University.
Supervised by
Dr Jochen Koenigsmann.
- Franziska Jahnke and Jochen Koenigsmann:
Definable henselian valuations.
The Journal of Symbolic Logic / Volume 80 / Issue 01 / March 2015, pp 85-99.
- Arno Fehm and Franziska Jahnke:
On almost small absolute Galois groups.
Israel Journal of Mathematics,
July 2016, Volume 214, Issue 1, pp. 193-207.
- Franziska Jahnke and Jochen Koenigsmann:
Uniformly defining p-henselian valuations.
Annals of Pure and Applied Logic 166 (2015), pp. 741-754.
- Franziska Jahnke:
Uniformly defining p-henselian valuations (joint work with Jochen
Koenigsmann).
Extended abstract, Oberwolfach Report (4) 2014, pp. 2788-2789.
- Arno Fehm and Franziska Jahnke:
On the quantifier complexity of definable canonical henselian valuations.
Mathematical Logic Quarterly 61 (4-5/2015), pp. 347-361.
- Franziska Jahnke and Jochen Koenigsmann:
Defining coarsenings of valuations.
Proceedings of the Edinburgh Mathematical Society, August 2017,
Volume 60, Issue 3, pp. 665-687.
- Immanuel Halupczok and Franziska Jahnke:
A definable henselian valuation
with high quantifier complexity.
Mathematical Logic Quarterly 61 (4-5/2015), pp. 362-366.
- Franziska Jahnke, Pierre Simon and Erik Walsberg:
Dp-minimal valued fields.
The Journal of Symbolic Logic / Volume 82 / Issue 01 / March 2017, pp. 151-165.
- Sylvy Anscombe and Franziska Jahnke:
Henselianity in the
language of rings.
Annals of Pure and Applied Logic 169 (2018), pp. 872-895.
- Franziska Jahnke:
When does dependence transfer from fields to henselian expansions?
Extended abstract, Oberwolfach Report (1) 2016, pp. 29-32.
- Franziska Jahnke and Pierre Simon:
NIP henselian valued fields.
Archive of Mathematical Logic, 59(1), 167-178 (2020).
- Franziska Jahnke:
When does NIP transfer from fields to henselian expansions?
To appear in Journal of Mathematical Logic.
- Arno Fehm and Franziska Jahnke:
Recent Progress on Definability of Henselian Valuations.
Survey article.
F. Broglia, F. Delon, M. Dickmann, D. Gondard, and V. Powers (eds.), Ordered Algebraic Structures and Related Topics, Contemporary Mathematics 697, 2017, pp. 135-143.
- Yatir Halevi, Assaf Hasson and Franziska Jahnke:
A conjectural classification of strongly dependent fields. Bulletin of Symbolic Logic 25 (2019), pp. 182-195.
- Yatir Halevi, Assaf Hasson and Franziska Jahnke:
Definable V-topologies, Henselianity and NIP. Journal of Mathematical Logic (2020), no. 2, 2050008, 33 pp.
- Sylvy Anscombe and Franziska Jahnke:
The Model Theory of Cohen rings. Confluentes Mathematici, 14.2 (2022), pp. 1–28.
- Sylvy Anscombe and Franziska Jahnke:
Characterizing NIP henselian fields. Preprint, 2021.
- Philip Dittmann, Franziska Jahnke, Sebastian Krapp and Salma Kuhlmann:
Definable valuations on ordered fields. To appear in Model Theory.
- Franziska Jahnke and Konstantinos Kartas: Beyond the Fontaine-Wintenberger Theorem, Preprint, 2023.
- Sylvy Anscombe, Philip Dittmann and Franziska Jahnke:
Ax-Kochen-Ershov principles for finitely ramified henselian fields, Preprint, 2023.
Textbook
- Franziska Jahnke: An introduction to valued fields, book chapter in Lectures in Model Theory (see next item), pp.
119 - 149.
- Franziska Jahnke, Daniel Palacin, Katrin Tent (editors):
Lectures in Model Theory. Published in the series
Münster Lectures in Mathematics of the European Mathematical
Society, 222 pages, ISBN 978-3-03719-184-2, April 2018.
Notes (not intended for publication)
PhD theses
Bachelor and Master theses
- Paul Edelbrock:
Infinite superstable fields are algebraically closed
Bachelor thesis, 2023.
- Antonia Bruns: Ringtheorie und Primfaktorzerlegung. Bachelor thesis (in German), 2023.
- Ines Brauer: On axioms for propositional logic. Bachelor thesis (in German), 2023.
- Luca Bast: Definability of the p-adic valuation in extensions of Qp.
Bachelor thesis (in German), 2023.
- Anna Sielenkämper: (Un)Decicability in the natural numbers. Master thesis (Master of Education), 2022.
- Karen Toben (TU Dortmund): Classification with p-adic neural networks: Applications to time series segmentations in traffic. Master thesis (in German, computer science), 2021,
co-supervision with JProf. Dr. Thomas Liebig.
- Mirco Frerichs: Fraisse-Limiten und die logische Betrachten des 0-1-Gesetzes auf Zufallsgraphen. Bachelor thesis (in German).
- Simone Ramello (University of Turin): Etale methods in the model theory of
fields. Master thesis, 2021, co-supervision with Prof. Dr. Martin Hils
- Florian Felix: A new approach to Ershov's wonderful fields.
Master thesis, 2021. Now PhD student at the HHU Düsseldorf.
- Fan Feng: Tree properties in model theory. Master thesis, 2020. Now PhD student at Leipzig University.
- Thomas Koch: NIP Körper und Henselität in positiver Charakteristik. Bachelor thesis (in German), 2020.
- Leon Pernak: Computable and elementary functions.
Bachelor thesis (in computer science), 2018.
- Florian Severin:
Varianten von Hensels Lemma. Master thesis (in German), 2016.
Now PhD student at the HHU Düsseldorf.
- Maurice Krause:
Komplexitätsklassen und Hierarchiesätze.
Bachelor thesis (in German), 2016. Now PhD student at the WWU Münster
- Justin Dreyer:
Hilbert's 10. Problem:
Diophantine sets are not decidable. Bachelor thesis (in German), 2016.
- 2004 - 2009:
Undergraduate student (Diplom) at the Albert-Ludwigs-Universität
Freiburg
- 2009 - 2013: DPhil student at Oxford University
- 2013 - 2017: Research assistant at the WWU Münster
- WS 2015/2016: Visiting professor at the WWU Münster
- since WS 2017/2018: Junior professor at the WWU Münster