Heavy Tails in Calabi-Yau Moduli Spaces

TL;DR

This paper investigates the statistical properties of the metric on Calabi-Yau moduli spaces, revealing heavy-tailed eigenvalue distributions and implications for vacuum stability in string theory compactifications.

Contribution

It introduces a novel triangulation algorithm enabling analysis of high-dimensional Calabi-Yau hypersurfaces and uncovers heavy-tailed spectra in the metric and curvature contributions.

Findings

Eigenvalues of the metric and curvature have heavy-tailed distributions.

Curvature contribution to the Hessian is non-positive, affecting metastability.

Algorithm allows analysis of hypersurfaces with h^{1,1} up to 25.

Abstract

We study the statistics of the metric on K\"ahler moduli space in compactifications of string theory on Calabi-Yau hypersurfaces in toric varieties. We find striking hierarchies in the eigenvalues of the metric and of the Riemann curvature contribution to the Hessian matrix: both spectra display heavy tails. The curvature contribution to the Hessian is non-positive, suggesting a reduced probability of metastability compared to cases in which the derivatives of the K\"ahler potential are uncorrelated. To facilitate our analysis, we have developed a novel triangulation algorithm that allows efficient study of hypersurfaces with $h^{1,1}$ as large as 25, which is difficult using algorithms internal to packages such as Sage. Our results serve as input for statistical studies of the vacuum structure in flux compactifications, and of the distribution of axion decay constants in string theory.