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arXiv · 2608.30330

Vertex-transitive strongly regular graphs in the switching class of doubly transitive two-graphs

Robert F. Bailey·Gábor P. Nagy·Valentino Smaldore
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Abstract

Let $G$ be a permutation group that acts $2$-transitively on the finite set $V$ and let $\mathcal{T}=(V,T)$ be a two-graph whose automorphism group contains $G$. In this paper, we classify those strongly regular graphs $\Gamma$ with vertex set $V$ whose automorphism group is a transitive maximal subgroup of $G$ and whose associated two-graph is $\mathcal{T}$. In doing so, we obtain a new family of vertex-transitive strongly regular graphs whose associated two-graph arises from $P\Sigma L(2,q)$.

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Robert F. Bailey, Gábor P. Nagy, Valentino Smaldore. 2026-08-31. Vertex-transitive strongly regular graphs in the switching class of doubly transitive two-graphs. https://arxiv.org/abs/2608.30330

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