{ "id": "1812.00330", "version": "v1", "published": "2018-12-02T05:17:02.000Z", "updated": "2018-12-02T05:17:02.000Z", "title": "On the module structure of the center of hyperelliptic Krichever-Novikov algebras II", "authors": [ "Ben Cox", "Xiangqian Guo", "Mee Seong Im", "Kaiming Zhao" ], "comment": "24 pages, submitted", "categories": [ "math.RT", "math-ph", "math.MP" ], "abstract": "Let $R := R_{2}(p)=\\mathbb{C}[t^{\\pm 1}, u : u^2 = t(t-\\alpha_1)\\cdots (t-\\alpha_{2n})] $ be the coordinate ring of a nonsingular hyperelliptic curve and let $\\mathfrak{g}\\otimes R$ be the corresponding current Lie algebra. \\color{black} Here $\\mathfrak g$ is a finite dimensional simple Lie algebra defined over $\\mathbb C$ and \\begin{equation*} p(t)= t(t-\\alpha_1)\\cdots (t-\\alpha_{2n})=\\sum_{k=1}^{2n+1}a_kt^k. \\end{equation*} In earlier work, Cox and Im gave a generator and relations description of the universal central extension of $\\mathfrak{g}\\otimes R$ in terms of certain families of polynomials $P_{k,i}$ and $Q_{k,i}$ and they described how the center $\\Omega_R/dR$ of this universal central extension decomposes into a direct sum of irreducible representations when the automorphism group was the cyclic group $C_{2k}$ or the dihedral group $D_{2k}$. We give examples of $2n$-tuples $(\\alpha_1,\\dots,\\alpha_{2n})$, which are the automorphism groups $\\mathbb G_n=\\text{Dic}_{n}$, $\\mathbb U_n\\cong D_n$ ($n$ odd), or $\\mathbb U_n$ ($n$ even) of the hyperelliptic curves \\begin{equation} S=\\mathbb{C}[t, u: u^2 = t(t-\\alpha_1)\\cdots (t-\\alpha_{2n})] \\end{equation} given in [CGLZ17]. In the work below, we describe this decomposition when the automorphism group is $\\mathbb U_n=D_n$, where $n$ is odd.", "revisions": [ { "version": "v1", "updated": "2018-12-02T05:17:02.000Z" } ], "analyses": { "keywords": [ "hyperelliptic krichever-novikov algebras", "module structure", "automorphism group", "finite dimensional simple lie algebra", "hyperelliptic curve" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable" } } }