English

Boundary zeros of stable polynomials in the unit ball

Complex Variables 2026-07-07 v1

Abstract

Interpolation theory in the unit ball and semi-algebraic geometry yield explicit descriptions of the boundary zeros of stable polynomials. Given a polynomial pC[z1,...,zn]p\in \mathbb{C}[z_1, ...,z_n] that is zero-free in the unit ball and vanishes on the sphere along submanifolds of dimension at most one, we describe the boundary zeros Z(p)Sn\mathcal{Z}(p)\cap\mathbb{S}_n in terms of peak sets for A(Bn)A^\infty(\mathbb{B}_n). In particular, in the setting n=2n=2, we achieve a characterization by proving that every accumulation point of Z(p)S2\mathcal{Z}(p)\cap\mathbb{S}_2 lies in the relative interior of an one dimensional real analytic submanifold, and that these submanifolds form a foliation of the non-isolated part of Z(p)S2\mathcal{Z}(p)\cap\mathbb{S}_2. As an application of the developed theory, we obtain a characterization of cyclic polynomials without weak essential singularities in the Dirichlet-type space Dn1/2(Bn)\mathcal{D}_{n-1/2}(\mathbb{B}_n). A theory for more general geometric settings of the boundary zeros is also developed, aiming to provide a starting point for further extensions.

Keywords

Cite

@article{arxiv.2607.05974,
  title  = {Boundary zeros of stable polynomials in the unit ball},
  author = {Dimitrios Vavitsas and Jujie Wu and Konstantinos Zarvalis},
  journal= {arXiv preprint arXiv:2607.05974},
  year   = {2026}
}

Comments

21 pages, 2 figures