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arXiv · 2211.07856

Linear $q$-difference, difference and differential operators preserving some $\mathcal{A}$-entire functions

Jiaxing Huang·Tuen Wai Ng
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Abstract

We apply Rossi's half-plane version of Borel's Theorem to study the zero distribution of linear combinations of $\mathcal{A}$-entire functions (Theorem 1.2). This provides a unified way to study linear $q$-difference, difference and differential operators (with entire coefficients) preserving subsets of $\mathcal{A}$-entire functions, and hence obtain several analogous results for the Hermite-Poulain Theorem to linear finite ($q$-)difference operators with polynomial coefficients. The method also produces a result on the existence of infinitely many non-real zeros of some differential polynomials of functions in certain sub-classes of $\mathcal{A}$-entire functions.

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Jiaxing Huang, Tuen Wai Ng. 2022-11-15. Linear $q$-difference, difference and differential operators preserving some $\mathcal{A}$-entire functions. https://arxiv.org/abs/2211.07856

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