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arXiv · 2605.05849

Spaces of matrices with few eigenvalues (II)

Clément de Seguins Pazzis
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Abstract

Let $F$ be a field, and $\mathcal{M}$ be a linear subspace of $n$-by-$n$ matrices with entries in $F$ that have at most two eigenvalues in $F$ (respectively, at most one non-zero eigenvalue in $F$). In a previous article, we have determined the greatest possible dimension for $\mathcal{M}$ when the characteristic of $F$ is not $2$. In this article and its sequel, we solve this problem for all fields with characteristic $2$.

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Clément de Seguins Pazzis. 2026-05-07. Spaces of matrices with few eigenvalues (II). https://arxiv.org/abs/2605.05849

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