Green functions, Segre numbers, and King's formula

TL;DR

This paper establishes a connection between Monge-Ampère products, Segre numbers, and King's formula in complex geometry, providing a new interpretation of Lelong numbers and extending classical results.

Contribution

It introduces a new interpretation of Monge-Ampère products in terms of Segre numbers and generalizes King's formula within complex geometry.

Findings

Lelong numbers of certain currents match Segre numbers

Monge-Ampère products are well-defined and meaningful in this context

Generalization of King's formula for these currents

Abstract

Let $\mathcal J$ be a coherent ideal sheaf on a complex manifold $X$ with zero set $Z$, and let $G$ be a plurisubharmonic function such that $G=\log|f|+\mathcal O(1)$ locally at $Z$, where $f$ is a tuple of holomorphic functions that defines $\mathcal J$. We give a meaning to the Monge-Amp\`{e}re products $(dd^c G)^k$ for $k=0,1,2,...$, and prove that the Lelong numbers of the currents $M_k^{\mathcal J}:=\mathbf 1_Z(dd^c G)^k$ at $x$ coincide with the so-called Segre numbers of $\mathcal J$ at $x$, introduced independently by Tworzewski, Gaffney-Gassler, and Achilles-Manaresi. More generally, we show that $M_k^{\mathcal J}$ satisfy a certain generalization of the classical King formula.