On the Complexity of Identifying Strongly Regular Graphs

Michael Levet

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arXiv · 2207.05930

On the Complexity of Identifying Strongly Regular Graphs

Michael Levet

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Abstract

In this paper, we show that Graph Isomorphism (GI) is not $\textsf{AC}^{0}$-reducible to several problems, including the Latin Square Isotopy problem, isomorphism testing of several families of Steiner designs, and isomorphism testing of conference graphs. As a corollary, we obtain that GI is not $\textsf{AC}^{0}$-reducible to isomorphism testing of Latin square graphs and strongly regular graphs arising from special cases of Steiner $2$-designs. We accomplish this by showing that the generator-enumeration technique for each of these problems can be implemented in $\beta_{2}\textsf{FOLL}$, which cannot compute Parity (Chattopadhyay, Tor\'an, & Wagner, ACM Trans. Comp. Theory, 2013).

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Michael Levet. 2022-07-13. On the Complexity of Identifying Strongly Regular Graphs. https://arxiv.org/abs/2207.05930

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