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arXiv · 2512.07669

On Borel orbits of quadratic forms in characteristic 2

Yasmine B. Sanderson
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Abstract

We consider the spherical variety of quadratic forms over a quadratically closed field of characteristic 2, and determine its orbits for the action of the Borel subgroup of upper triangular matrices. We exhibit a connection between these orbits and the Catalan triangle numbers. In addition, we describe explicitly a natural Weyl group action on the set of Borel orbit double covers

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Yasmine B. Sanderson. 2025-12-08. On Borel orbits of quadratic forms in characteristic 2. https://arxiv.org/abs/2512.07669

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