Asymptotics and Dimensional Dependence of the Number of Critical Points of Random Holomorphic Sections

TL;DR

This paper proves conjectures about the expected number of critical points of random holomorphic sections, showing their asymptotic behavior and dependence on dimension, with implications for string theory and spin glasses.

Contribution

It confirms conjectures on the asymptotics of critical points of random holomorphic sections and provides explicit growth rates and bounds for their expected counts.

Findings

Critical points of minimal Morse index are most numerous.

Expected number of critical points grows asymptotically with line bundle degree.

Results apply to both projective space and general Kähler manifolds.

Abstract

We prove two conjectures from [M. R. Douglas, B. Shiffman and S. Zelditch, Critical points and supersymmetric vacua, II: Asymptotics and extremal metrics. J. Differential Geom. 72 (2006), no. 3, 381-427] concerning the expected number of critical points of random holomorphic sections of a positive line bundle. We show that, on average, the critical points of minimal Morse index are the most plentiful for holomorphic sections of ${\mathcal O}(N) \to \CP^m$ and, in an asymptotic sense, for those of line bundles over general K\"ahler manifolds. We calculate the expected number of these critical points for the respective cases and use these to obtain growth rates and asymptotic bounds for the total expected number of critical points in these cases. This line of research was motivated by landscape problems in string theory and spin glasses.