{ "id": "1610.06248", "version": "v1", "published": "2016-10-19T23:55:58.000Z", "updated": "2016-10-19T23:55:58.000Z", "title": "Pairing between zeros and critical points of random polynomials with independent roots", "authors": [ "Sean O'Rourke", "Noah Williams" ], "comment": "38 pages, 5 figures", "categories": [ "math.PR" ], "abstract": "Let $p_n$ be a random, degree $n$ polynomial whose roots are chosen independently according to the probability measure $\\mu$ on the complex plane. For a deterministic point $\\xi$ lying outside the support of $\\mu$, we show that almost surely the polynomial $q_n(z):=p_n(z)(z - \\xi)$ has a critical point at distance $O(1/n)$ from $\\xi$. In other words, conditioning the random polynomials $p_n$ to have a root at $\\xi$, almost surely forces a critical point near $\\xi$. More generally, we prove an analogous result for the critical points of $q_n(z):=p_n(z)(z - \\xi_1)\\cdots (z - \\xi_k)$, where $\\xi_1, \\ldots, \\xi_k$ are deterministic. In addition, when $k=o(n)$, we show that the empirical distribution constructed from the critical points of $q_n$ converges to $\\mu$ in probability as the degree tends to infinity, extending a recent result of Kabluchko.", "revisions": [ { "version": "v1", "updated": "2016-10-19T23:55:58.000Z" } ], "analyses": { "keywords": [ "critical point", "random polynomials", "independent roots", "probability measure", "deterministic point" ], "note": { "typesetting": "TeX", "pages": 38, "language": "en", "license": "arXiv", "status": "editable" } } }