{ "id": "1512.03469", "version": "v1", "published": "2015-12-10T22:31:43.000Z", "updated": "2015-12-10T22:31:43.000Z", "title": "Complete classification of $H$-type algebras: I", "authors": [ "Kenro Furutani", "Irina Markina" ], "comment": "38 pages", "categories": [ "math.RT" ], "abstract": "Let $\\mathscr N$ be a 2-step nilpotent Lie algebra endowed with non-degenerate scalar product $\\langle.\\,,.\\rangle$ and let $\\mathscr N=V\\oplus_{\\perp}Z$, where $Z$ is the centre of the Lie algebra and $V$ its orthogonal complement with respect to the scalar product. We study the classification of the Lie algebras for which the space $V$ arises as a representation space of a Clifford algebra $\\Cl(\\mathbb R^{r,s})$ and the representation map $J\\colon \\Cl(\\mathbb R^{r,s})\\to(V)$ is related to the Lie algebra structure by $\\langle J_zv,w\\rangle=\\langle z,[v,w]\\rangle$ for all $z\\in \\mathbb R^{r,s}$ and $v,w\\in V$. The classification is based on the range of parameters $r$ and $s$ and is completed for the Clifford modules $V$, having minimal possible dimension, that are not necessary irreducible. We find the necessary condition for the existence of a Lie algebra isomorphism according to the range of integer parameters $0\\leq r,s<\\infty$. We present the constructive proof for the isomorphism map for isomorphic Lie algebras and defined the class of non-isomorphic Lie algebras.", "revisions": [ { "version": "v1", "updated": "2015-12-10T22:31:43.000Z" } ], "analyses": { "subjects": [ "17B60", "17B30", "17B70", "22E15" ], "keywords": [ "type algebras", "complete classification", "lie algebra isomorphism", "lie algebra structure", "nilpotent lie algebra" ], "note": { "typesetting": "TeX", "pages": 38, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv151203469F" } } }