English

A geometric criterion on the equality between BKK bound and intersection index

Algebraic Geometry 2023-04-19 v2 Combinatorics

Abstract

The Bernshtein-Kushnirenko-Khovanskii theorem provides a generic root count for system of Laurent polynomials in terms of the mixed volume of their Newton polytopes (i.e., the BKK bound). A recent and far-reaching generalization of this theorem is the study of birationally invariant intersection index by Kaveh and Khovanskii. This short note establishes a simple geometric condition on the equality between the BKK bound and the intersection index for a system of vector spaces of Laurent polynomials. Applying this, we show that the intersection index for the algebraic Kuramoto equations equals their BKK bound.

Keywords

Cite

@article{arxiv.1812.05408,
  title  = {A geometric criterion on the equality between BKK bound and intersection index},
  author = {Tianran Chen},
  journal= {arXiv preprint arXiv:1812.05408},
  year   = {2023}
}
R2 v1 2026-06-23T06:41:24.661Z