{ "id": "2203.09651", "version": "v1", "published": "2022-03-17T23:19:38.000Z", "updated": "2022-03-17T23:19:38.000Z", "title": "Local-global principles for hermitian spaces over semi-global fields", "authors": [ "Jayanth Guhan", "V. Suresh" ], "categories": [ "math.AG", "math.AC", "math.NT", "math.RA" ], "abstract": "Let $K$ be a complete discrete valued field with residue field $k$ and $F$ the function field of a curve over $K$. Let $A \\in {}_2Br(F)$ be a central simple algebra with an involution $\\sigma$ of any kind and $F_0 =F^{\\sigma}$. Let $h$ be an hermitian space over $(A, \\sigma)$ and $G = SU(A, \\sigma, h)$ if $\\sigma$ is of first kind and $G = U(A, \\sigma, h)$ if $\\sigma$ is of second kind. Suppose that $\\text{char}(k) \\neq 2$ and ind$(A)\\leq 4$. Then we prove that projective homogeneous spaces under $G$ over $F_0$ satisfy a local-global principle for rational points with respect to discrete valuations of $F$.", "revisions": [ { "version": "v1", "updated": "2022-03-17T23:19:38.000Z" } ], "analyses": { "keywords": [ "local-global principle", "hermitian space", "semi-global fields", "central simple algebra", "complete discrete valued field" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }