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arXiv · 2505.05641

Finiteness theorems for some representations of $\mathrm{GL}_3$

Fatemehzahra Janbazi·Arul Shankar
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Abstract

Let $n \geq 2$ be an integer and let $K$ be a number field with ring of integers $\mathcal{O}_K$. We prove that the set of ternary $n$-ic forms with coefficients in $\mathcal{O}_K$ and fixed nonzero discriminant, breaks up into finitely many $\mathrm{GL}_3(\mathcal{O}_K)$-orbits. This generalizes a result of Birch--Merriman in the binary forms case. We also prove a similar finiteness result on the $\mathrm{GL}_3(\mathcal{O}_K)$-orbits of the 27-dimensional representation of $\mathrm{GL}_3$ with highest weight $(4, 2)$.

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Fatemehzahra Janbazi, Arul Shankar. 2025-05-08. Finiteness theorems for some representations of $\mathrm{GL}_3$. https://arxiv.org/abs/2505.05641

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