My name is Sean Cotner and I'm a graduate student at Stanford
, advised by Brian Conrad
I am interested in group schemes, broadly construed. In particular, I am interested in reductive groups and finite locally free group schemes.
My e-mail address is scotner at stanford dot edu.
Publications and Preprints
- Springer isomorphisms over a general base scheme (arxiv).
- Lifting \(G\)-valued representations when \(\ell \neq p\), with Jeremy Booher and Shiang Tang (arxiv).
- Lefschetz theorems in flat cohomology and applications, with Bogdan Zavyalov (arxiv).
- Centralizers of sections of a reductive group scheme (arxiv).
Some expository writing
- Mod \(p\) representations of finite groups of Lie type (pdf).
These notes explain Steinberg's theorem parameterizing irreducible representations of finite groups of Lie type in their defining characteristic. Written around February 2021.
Occasionally I blog about math at Thuses
This website design was stolen (with permission) from Pol van Hoften
(who stole it (with permission) from Ashwin Iyengar