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Deterministic structural trigger for cutoff on random graphs (derandomization)

Identify a deterministic structural property that is almost surely satisfied by standard sparse random graph models (such as random regular graphs or related sparse ensembles) and that, when verified on a specific graph instance, deterministically implies total-variation cutoff for the simple random walk on that graph.

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Background

Recent advances exploit the tree-like geometry of sparse random graphs to prove cutoff for simple random walk in various models. However, these proofs are tailored to randomness and do not provide a general deterministic structure that guarantees cutoff. The notes call for a structural condition that can be checked deterministically and that these random graphs satisfy with high probability.

References

While this has led to rigorous proofs of cutoff in several models, the common mechanism at play behind all those instances has not yet been identified.

Modern aspects of Markov chains: entropy, curvature and the cutoff phenomenon (2508.21055 - Salez, 28 Aug 2025) in Section 2.1, Random walks on graphs (end of the paragraph on random graphs)