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arXiv · 2011.13245

Stiefel Whitney Classes for Real representations of $\mathrm{GL}_2(\mathbb{F}_q)$

Jyotirmoy Ganguly·Rohit Joshi
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Abstract

We compute the total Stiefel Whitney class for a real representation $\pi$ of $\mathrm{GL}_2(\mathbb{F}_q)$, where $q$ is odd. The obstruction class of $\pi$ is defined to be the Stiefel Whitney class of lowest positive degree that does not vanish. We provide an expression for the obstruction class of $\pi$ in terms of its character values if $\det\pi=1$.

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BibTeXRIS

Jyotirmoy Ganguly, Rohit Joshi. 2020-11-26. Stiefel Whitney Classes for Real representations of $\mathrm{GL}_2(\mathbb{F}_q)$. https://arxiv.org/abs/2011.13245

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