Hironaka's golden ratio conjecture for minimum dilatations

For each genus gg, let δg,0\delta_{g,0} denote the minimum dilatation among pseudo-Anosov maps on the closed surface of genus gg, and let μ\mu be the golden ratio. Hironaka's golden ratio conjecture. The minimum dilatations satisfy

limgδg,02g2=μ4.\lim_{g\to\infty}\delta_{g,0}^{2g-2}=\mu^4.

This conjecture predicts the asymptotic minimum normalized dilatation for pseudo-Anosov maps on closed surfaces. The source notes that examples with a uniformly bounded number of singularities support an approach to proving it, but the conjecture remains open in the supplied text.

Sources & referencesView supporting material

Primary source

Chi Cheuk Tsang, “On the set of normalized dilatations of fully-punctured pseudo-Anosov maps”, arXiv:2306.10245 (2025).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.