First eigenvalue of the Laplacian on compact surfaces for large genera

Antonio Ros

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arXiv · 2211.15172

First eigenvalue of the Laplacian on compact surfaces for large genera

Antonio Ros

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Abstract

For any Riemannian metric $ds^2$ on a compact surface of genus $g$, Yang and Yau proved that the normalized first eigenvalue of the Laplacian $λ_1(ds^2)Area(ds^2)$ is bounded in terms of the genus. In particular, if $Λ_1(g)$ is the supremum for each $g$, it follows that the asymptotic growth of the sequence ${Λ_1(g)}$ is no larger than the one of $4πg$. In this paper we improve the result and we show that \[ \limsup_{g\, \rightarrow\, \infty} \, \frac{1}{g}Λ_1(g) \leq 4(3-\sqrt{5})π\approx 3.056π. \]

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Antonio Ros. 2022-12-01. First eigenvalue of the Laplacian on compact surfaces for large genera. https://arxiv.org/abs/2211.15172

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