{ "id": "math/0503026", "version": "v1", "published": "2005-03-02T00:21:51.000Z", "updated": "2005-03-02T00:21:51.000Z", "title": "Cubic equations for the hyperelliptic locus", "authors": [ "Samuel Grushevsky" ], "journal": "Asian J Math, vol 8 (2004) no. 1, special issue dedicated to Yum-Tong Siu on his 60th birthday", "categories": [ "math.AG" ], "abstract": "We discuss the conjecture of Buchstaber and Krichever that their multi-dimensional vector addition formula for Baker-Akhiezer functions characterizes Jacobians among principally polarized abelian varieties, and prove that it is indeed a weak characterization, i.e. that it is true up to additional components, or true precisely under a general position assumption. We also show that this addition formula is equivalent to Gunning's multisecant formula for the Kummer variety. We then use Buchstaber-Krichever's computation of the coefficients in the addition formula to obtain cubic relations among theta functions, which (weakly) characterize the locus of hyperelliptic Jacobians among irreducible abelian varieties. In genus 3 our equations are equivalent to the vanishing of one theta-null, and thus are known classically by work of Mumford and Poor, but already for genus 4 they appear to be new.", "revisions": [ { "version": "v1", "updated": "2005-03-02T00:21:51.000Z" } ], "analyses": { "keywords": [ "hyperelliptic locus", "cubic equations", "multi-dimensional vector addition formula", "baker-akhiezer functions characterizes jacobians", "general position assumption" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math......3026G" } } }