Workshop on Prismatic Cohomology

We will study prismatic cohomology, a new cohomology theory developed by Bhargav Bhatt and Peter Scholze. There will be 10 talks, see below for further details.

Organizers: Eike Lau, Torsten Wedhorn, Eva Viehmann / Ulrich Görtz (local organizer)

Date: March 27 – 29, 2019 (We will start on Wednesday at 10am, and the workshop will end on Friday around 2pm)

Place: Department of Mathematics, University of Duisburg-Essen (Thea-Leymann-Str. 9, 45127 Essen)

Program: pdf


If you are interested in attending, please send an email to Ulrich Görtz,, so that we can keep track of how many people will be around and order enough coffee for the coffee breaks.


Most participants are in B&B Hotel Essen, Helmut-Käutner-Straße 4, 45127 Essen (very close to the math department), Phone: 0201 616960. If you have not yet booked a room, you should contact the hotel as soon as possible. We have reserved a few more rooms until Friday, Feb. 8 (mention “Math Institute/Prof. Görtz”).


All talks will take place in the math building of the University of Duisburg-Essen, Thea-Leymann-Str. 9/Altendorfer Str. 11, 45127 Essen, seminar room N-U-3.04 (3rd floor, north wing).

To get to the math department from the main station, take the U-Bahn to Berliner Platz. From there, walk down Altendorfer Str. In the ground floor of the building, there is a large Conrad Electronics store, so the building is easy to find.

Talks and schedule

1 $\delta$-rings Jakob Stix (Frankfurt) Wednesday 10:00 – 11:15
2 Derived completion Jens Hesse (Darmstadt) 11:45 – 12:45
3 Prisms Maria Beckemeyer (Münster) + Karsten Schrödter (Bielefeld) 14:45 – 16:00
4 The prismatic site and the Hodge-Tate comparison map Matteo Tamiozzo (Essen) 16:30 – 17:30
5 Crystalline and Hodge-Tate comparison maps Lennart Gehrmann (Essen) Thursday 9:30 – 10:45
6 Non-abelian derived functors Fritz Hörmann (Freiburg) 11:15 – 12:45
7 Derived prismatic cohomology Kay Rülling (FU Berlin) 15:00 – 16:00
8 Application to perfectoid rings Paul Hamacher (TU München) 16:30 – 17:30
9 Étale comparison Johannes Anschütz (Bonn) Friday 9:30 – 10:45
10 Application: $q$-de Rham cohomology Andreas Pieper (Ulm) 11:15 – 12:30