{ "id": "2310.10361", "version": "v1", "published": "2023-10-16T12:56:55.000Z", "updated": "2023-10-16T12:56:55.000Z", "title": "Linear system of hypersurfaces passing through a Galois orbit", "authors": [ "Shamil Asgarli", "Dragos Ghioca", "Zinovy Reichstein" ], "comment": "12 pages", "categories": [ "math.AG", "math.NT" ], "abstract": "Let $d$ and $n$ be positive integers, and $E/F$ be a separable field extension of degree $m=\\binom{n+d}{n}$. We show that if $|F| > 2$, then there exists a point $P\\in \\mathbb{P}^n(E)$ which does not lie on any degree $d$ hypersurface defined over $F$. In other words, the $m$ Galois conjugates of $P$ impose independent conditions on the $m$-dimensional $F$-vector space of degree $d$ forms in $x_0, x_1, \\ldots, x_n$. As an application, we determine the maximal dimension of an $F$-linear system $\\mathcal{L}$ of hypersurfaces such that every $F$-member of $\\mathcal{L}$ is irreducible over $F$.", "revisions": [ { "version": "v1", "updated": "2023-10-16T12:56:55.000Z" } ], "analyses": { "subjects": [ "14N05", "14J70", "14G15" ], "keywords": [ "linear system", "galois orbit", "hypersurfaces passing", "impose independent conditions", "separable field extension" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }