I am a postdoc at the University Bielefeld, Germany, in the BIREP group.

In 2020 I finished my PhD at the University of Utah. There I studied commutative algebra with Srikanth Iyengar. The title of my thesis is Generation Time in Derived Categories.

I obtained a Bachelor in Mathematics in 2014 and a Bachelor in Physics in 2015 from the Johannes Gutenberg University Mainz, Germany.

I am interested in triangulated, derived, and stable categories.

Here is my CV.



  1. Brown representability for triangulated categories with a linear action by a graded ring
    arXiv:2206.09646 (submitted)
  2. The spectrum of a well-generated tensor triangulated category with Henning Krause
    arXiv:2203.03249 (submitted)
  3. Exceptional complete intersection maps of local rings with Srikanth Iyengar, Jian Liu, Josh Pollitz
    arXiv:2107.07354 (submitted)
  4. Appendices in Maximal Cohen–Macaulay Modules and Tate Cohomology by Ragnar-Olaf Buchweitz with Luchezar Avramov, Ben Briggs, Srikanth Iyengar
    in Mathematical Surveys and Monographs, American Mathematical Society
  5. Locally Complete Intersection Maps and the Proxy Small Property with Ben Briggs, Srikanth Iyengar, Josh Pollitz
    in International Mathematics Research Notices, pages 1–28, 2021. Advance article
  6. Local to global principles for generation time over Noether algebras
    in Homology, Homotopy and Applications, 23(2): 165–182, 2021

Current and Upcoming

Co-organizer of Representation Theory and Triangulated Categories
Paderborn, Germany—September 26–30, 2022
This is a conference in honour of Henning Krause's 60th birthday. I am organizing this conference together with Dave Benson, Igor Burban, Bill Crawley-Boevey, Eleonore Faber, Lutz Hille, Srikanth Iyengar, and Marc Stephan.
Participant of the trimester program Spectral Methods in Algebra, Geometry, and Topology
Hausdorff Research Institute for Mathematics, Bonn, Germany—September 12–December 16, 2022

Past talks.
Past conferences.
Past position, activities and resources.


jletz [at] math [dot] uni-bielefeld [dot] de
Mailing Address
Faculty of Mathematics
Bielefeld University
PO Box 100 131
33501 Bielefeld