{ "id": "1901.00901", "version": "v1", "published": "2019-01-03T20:12:54.000Z", "updated": "2019-01-03T20:12:54.000Z", "title": "Global existence of the harmonic map heat flow into Lorentzian manifolds", "authors": [ "Xiaoli Han", "Juergen Jost", "Lei Liu", "Liang Zhao" ], "comment": "to appear in J. Math. Pures Appl", "categories": [ "math.DG" ], "abstract": "We investigate a parabolic-elliptic system for maps $(u,v)$ from a compact Riemann surface $M$ into a Lorentzian manifold $N\\times{\\mathbb{R}}$ with a warped product metric. That system turns the harmonic map type equations into a parabolic system, but keeps the $v$-equation as a nonlinear second order constraint along the flow. We prove a global existence result of the parabolic-elliptic system by assuming either some geometric conditions on the target Lorentzian manifold or small energy of the initial maps. The result implies the existence of a Lorentzian harmonic map in a given homotopy class with fixed boundary data.", "revisions": [ { "version": "v1", "updated": "2019-01-03T20:12:54.000Z" } ], "analyses": { "keywords": [ "harmonic map heat flow", "global existence", "nonlinear second order constraint", "parabolic-elliptic system", "harmonic map type equations" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }