output
20242026
most citedGroup schemes over LG-rings and applications to cancellation theorems and Azumaya algebras

1 citations

6 papers

math.AG2026

Quadratic Spaces and Orthogonal Groups over semilocal Rings

Philippe Gille, Erhard Neher

We prove Springer's Odd Degree Theorem for quadratic forms over LG rings, and Scharlau's and Knebusch's norm principles for quadratic forms over semilocal rings. We present applica…

math.AG2025

Non-Stable -Functors of Discrete Valuation Rings Containing a Field

Philippe Gille, Anastasia Stavrova

Let be a field, and let be a simply connected semisimple k-group which is isotropic and contains a strictly proper parabolic -subgroup . Let be a discrete valuati…

math.AG2024

Loop torsors. Theory and applications

Philippe Gille, Vladimir Chernousov, Arturo Pianzola

Loop torsors over Laurent polynomial rings in characteristic 0 were originally introduced in relation to infinite dimensional Lie theory. Applications to other areas require a theo…

math.AG2024★ 1 cited

Group schemes over LG-rings and applications to cancellation theorems and Azumaya algebras

Philippe Gille, Erhard Neher

We prove several results on reductive group schemes over LG-rings, e.g., existence of maximal tori and conjugacy of parabolic subgroups. These were proven in SGA3 for the special c…

math.AG2024

Local-global principle for over semiglobal fields

Philippe Gille, Raman Parimala

We compare different local-global principles for torsors under a reductive group G defined over a semiglobal field F. In particular if the F-group G s a retract rational F-variety,…

math.AG2024

Loop torsors and Abhyankar's lemma

Philippe Gille

We define the notion of loop torsors under certain group schemes defined over the localization of a regular henselian ring A at a strict normal crossing divisor D. We provide a Gal…