Johannes Flake member of the [SFB-TRR 195](https://www.computeralgebra.de/sfb/) Postdoc at RWTH Aachen PhD from Rutgers University (2018) with Siddhartha Sahi Algebra and Representation Theory RWTH Aachen University Pontdriesch 10--16, 52062 Aachen, Germany Office: room 402, building no. 1952 Email: second name at art dot rwth minus aachen dot de [workshop](http://deligne-categories-quantum-groups.rwth-aachen.de/) Deligne categories and quantum groups (postponed due to COVID-19)

Research I am interested in algebra and representation theory, more specifically: - tensor categories, Deligne's interpolation categories, monoidal centers - algebraic Dirac operators, Dirac cohomology, cohomology functors - PBW deformations, various kinds of Hecke and Cherednik algebras - "easy quantum groups", diagram algebras - p-groups - computer algebra (arxiv:2106.05798) with Robert Laugwitz and Sebastian Posur: Indecomposable objects in Khovanov--Sazdanovic's generalizations of Deligne's interpolation categories (2021) (arxiv:2105.10492) with Nate Harman and Robert Laugwitz: The indecomposable objects in the center of Deligne's category Rep(S_t) (2021) (arxiv:2105.09117) with Dominik Bernhardt, Tim Boykett, Alice Devillers, Stephen Glasby: Groups G satisfying a functional equation f(xk)=xf(x) for some k in G (2021) (arxiv:2003.13798) with Laura Maaßen: Semisimplicity and indecomposable objects in interpolating partition categories (2020) (arxiv:2003.13297) with Andrea Thevis: Strata of p-Origamis (2020) (arxiv:2003.05639) with Ghislain Fourier and Viktor Levandovskyy: Gröbner bases for fusion products (2020) (arxiv:1608.07504) with Siddhartha Sahi: Hopf--Hecke algebras, infinitesimal Cherednik algebras and Dirac cohomology. Pure Appl. Math. Q., Kostant edition (in press). [article](https://londmathsoc.onlinelibrary.wiley.com/doi/full/10.1112/jlms.12403)(arxiv:1901.08657) with Robert Laugwitz: On the monoidal center of Deligne's category Rep(S_t). J. London Math. Soc. (2020). [article](https://www.ams.org/journals/tran/2019-371-10/S0002-9947-2019-07446-9/home.html)(arxiv:1608.07509) Barbasch--Sahi algebras and Dirac cohomology. Trans. Amer. Math. Soc. 371.10 (2019): 6883--6902. [PhD thesis](https://rucore.libraries.rutgers.edu/rutgers-lib/59087/) Dirac cohomology for Hopf--Hecke algebras, September 2018.

Teaching RWTH - Spring 2021: Algebraic Geometry [course page](https://www.art.rwth-aachen.de/cms/MATHB/Studium/Lehrveranstaltungen/Veranstaltungen-im-Sommersemester/~maona/Algebraische-Geometrie/?lidx=1) - Spring 2019: Lecture in Pairs on filtered-graded transfer and PBW deformations with Viktor Levandovskyy - Spring 2019: Begleitpraktikum 2 - Fall 2018: Begleitpraktikum Rutgers - Spring 2018: TA for Math 351 -- Introduction to Abstract Algebra I - Fall 2017: TA for Math 351 -- Introduction to Abstract Algebra I - Fall 2017: TA for Math 451 -- Abstract Algebra I - Spring 2017: TA for Math 311 -- Introduction to Real Analysis I - Spring 2017: TA-at-large for Math 354 -- Linear Optimization - Fall 2016: TA-at-large for Math 421 -- Advanced Calculus for Engineering - Spring 2016: TA for Math 251 -- Multivariable Calculus - Fall 2015: TA for Math 152 -- Calculus II for the Mathematical and Physical Sciences

Misc [johannesflake/oscar](https://github.com/johannesflake/oscar-docker/), my personal unofficial [OSCAR] docker image [polybases.jl](https://gitlab.com/johannesflake/polybases.jl), a Julia package for monomial bases using [OSCAR] and [polymake] (under development; [example](https://nbviewer.jupyter.org/github/johannesflake/polybases-examples/blob/master/polybases-example-1.ipynb)) [KnopCategoriesForGap](https://github.com/homalg-project/KnopCategoriesForCAP), a [GAP]/[CAP] package for Knop’s tensor envelopes [slides](pdf/schur_weyl_links.pdf) on quantum Schur--Weyl duality and link invariants [slides](pdf/deligne_category_rep_st.pdf) on Deligne's category Rep(S_t) [slides](pdf/voa_constructions.pdf) on some constructions of vertex operator algebras and their modules [slides](pdf/quantum_groups.pdf) on quantum groups and tensor categories [3d rendering](./misc/3d/index.html) of affine surfaces [visualization](./misc/tsp25/index.html) of my implementaton of an 2.5-opt algorithm approximately solving a random traveling salesman problem live in your browser (slowed down for visualization purposes) [... which traveling salesman?](https://www.quantamagazine.org/computer-scientists-find-new-shortcuts-to-traveling-salesman-problem-20130129/) [pictures](./misc/UDG/index.html) of some D6-symmetric unit-distance graphs in the plane with 745 vertices and chromatic number five that I discovered with a SAT solver [... so what?](https://www.quantamagazine.org/decades-old-graph-problem-yields-to-amateur-mathematician-20180417/) [pictures and video](./misc/mandelbrot/index.html) of the Mandelbrot set I made with Julia (the language) [... what am I looking at?](https://youtu.be/NGMRB4O922I) If you are interested in my five cents on web comics, nothing will ever beat this [xkcd](https://xkcd.com/1012/).