English

Discrete Invariants of Generically Inconsistent Systems of Laurent Polynomials

Algebraic Geometry 2018-10-02 v2 Combinatorics

Abstract

Let A1,,Ak \mathcal{A}_1, \ldots, \mathcal{A}_k be finite sets in Zn \mathbb{Z}^n and let Y(C)n Y \subset (\mathbb{C}^*)^n be an algebraic variety defined by a system of equations f1==fk=0, f_1 = \ldots = f_k = 0, where f1,,fk f_1, \ldots, f_k are Laurent polynomials with supports in A1,,Ak\mathcal{A}_1, \ldots, \mathcal{A}_k. Assuming that f1,,fk f_1, \ldots, f_k are sufficiently generic, the Newton polyhedron theory computes discrete invariants of Y Y in terms of the Newton polyhedra of f1,,fk f_1, \ldots, f_k . It may appear that the generic system with fixed supports A1,,Ak \mathcal{A}_1, \ldots, \mathcal{A}_k is inconsistent. In this paper, we compute discrete invariants of algebraic varieties defined by system of equations which are generic in the set of consistent system with support in A1,,Ak\mathcal{A}_1, \ldots, \mathcal{A}_k by reducing the question to the Newton polyhedra theory. Unlike the classical situation, not only the Newton polyhedra of f1,,fkf_1,\dots,f_k, but also the supports A1,,Ak\mathcal{A}_1, \ldots, \mathcal{A}_k themselves appear in the answers.

Keywords

Cite

@article{arxiv.1703.06392,
  title  = {Discrete Invariants of Generically Inconsistent Systems of Laurent Polynomials},
  author = {Leonid Monin},
  journal= {arXiv preprint arXiv:1703.06392},
  year   = {2018}
}

Comments

10 pages, subsection 4.1 is added, comments are welcome