{ "id": "1409.4170", "version": "v1", "published": "2014-09-15T08:07:00.000Z", "updated": "2014-09-15T08:07:00.000Z", "title": "Minimal Lagrangian submanifolds via the geodesic Gauss map", "authors": [ "Chris Draper", "Ian McIntosh" ], "comment": "15 pages", "categories": [ "math.DG", "math.SG" ], "abstract": "For an oriented isometric immersion $f:M\\to S^n$ the spherical Gauss map is the Legendrian immersion of its unit normal bundle $UM^\\perp$ into the unit sphere subbundle of $TS^n$, and the geodesic Gauss map $\\gamma$ projects this into the manifold of oriented geodesics in $S^n$ (the Grassmannian of oriented 2-planes in $\\mathbb{R}^{n+1}$), giving a Lagrangian immersion of $UM^\\perp$ into a Kaehler-Einstein manifold. We give expressions for the mean curvature vectors for both the spherical and geodesic Gauss maps in terms of the second fundamental form of $f$, and show that when $f$ has conformal shape form this depends only on the mean curvature of $f$. We deduce conditions under which $\\gamma$ is a minimal Lagrangian immersion. We give simple proofs that: deformations of $f$ always correspond to Hamiltonian deformations of $\\gamma$; the mean curvature vector of $\\gamma$ is always a Hamiltonian vector field. This extends work of Palmer on the case when $M$ is a hypersurface.", "revisions": [ { "version": "v1", "updated": "2014-09-15T08:07:00.000Z" } ], "analyses": { "subjects": [ "53C42", "53D12" ], "keywords": [ "geodesic gauss map", "minimal lagrangian submanifolds", "mean curvature vector", "second fundamental form", "conformal shape form" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1409.4170D" } } }