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arXiv · 2206.06626

On finite generalized quadrangles with $\mathrm{PSL}(2,q)$ as an automorphism group

Tao Feng·Jianbing Lu
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Abstract

Let $\mathcal{S}$ be a finite thick generalized quadrangle, and suppose that $G$ is an automorphism group of $\mathcal{S}$. If $G$ acts primitively on both the points and lines of $\mathcal{S}$, then it is known that $G$ must be almost simple. In this paper, we show that if the socle of $G$ is $\mathrm{PSL}(2,q)$ with $q\geq4$, then $q=9$ and $\mathcal{S}$ is the unique generalized quadrangle of order $2$.

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Tao Feng, Jianbing Lu. 2023-03-20. On finite generalized quadrangles with $\mathrm{PSL}(2,q)$ as an automorphism group. https://arxiv.org/abs/2206.06626

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