{ "id": "2307.07118", "version": "v1", "published": "2023-07-14T01:48:35.000Z", "updated": "2023-07-14T01:48:35.000Z", "title": "Lifting problem for universal quadratic forms over totally real cubic number fields", "authors": [ "Daejun Kim", "Seok Hyeong Lee" ], "comment": "12 pages", "categories": [ "math.NT" ], "abstract": "Lifting problem for universal quadratic forms asks for totally real number fields $K$ that admit a positive definite quadratic form with coefficients in $\\mathbb{Z}$ that is universal over the ring of integers of $K$. In this paper, we show that $K=\\mathbb{Q}(\\zeta_7+\\zeta_7^{-1})$ is the only such totally real cubic field. Moreover, we show that there is no such biquadratic field.", "revisions": [ { "version": "v1", "updated": "2023-07-14T01:48:35.000Z" } ], "analyses": { "subjects": [ "11E12", "11R16", "11H06", "11H55" ], "keywords": [ "totally real cubic number fields", "lifting problem", "universal quadratic forms asks", "real number fields" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }