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arXiv · 2501.04301

On extensions of principal series representations

Gautam H. Borisagar·Asfak Soneji
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Abstract

We compute $\mathrm{Ext}^{1}_B(\chi_1,\chi_2)$ between two characters $\chi_1,\chi_2$ of a Borel subgroup $B$ of a split reductive group $G$ over a finite field $\mathbb{F}_q,$ and make an application to the calculation of $\mathrm{Ext}^1_G(\pi_1,\pi_2)$ between principal series representations $\pi_1,\pi_2$ of $G(\mathbb{F}_q).$

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BibTeXRIS

Gautam H. Borisagar, Asfak Soneji. 2025-01-08. On extensions of principal series representations. https://doi.org/10.1007/s00013-025-02210-1

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