{ "id": "2411.12511", "version": "v1", "published": "2024-11-19T13:52:42.000Z", "updated": "2024-11-19T13:52:42.000Z", "title": "A Calderón Problem for Beltrami Fields", "authors": [ "Alberto Enciso", "Carlos Valero" ], "categories": [ "math.AP", "math.DG" ], "abstract": "On a $3$-dimensional Riemannian manifold with boundary, we define an analogue of the Dirichlet-to-Neumann map for Beltrami fields, which are the eigenvectors of the curl operator and play a major role in fluid mechanics. This map sends the normal component of a Beltrami field to its tangential component on the boundary. In this paper we establish two results showing how this normal-to-tangential map encodes geometric information on the underlying manifold. First, we show that the normal-to-tangential map is a pseudodifferential operator of order zero on the boundary whose total symbol determines the Taylor series of the metric at the boundary. Second, we go on to show that a real-analytic simply connected $3$-manifold can be reconstructed from its normal-to-tangential map. Interestingly, since Green's functions do not exist for the Beltrami field equation, a key idea of the proof is to find an appropriate substitute, which turn out to have a natural physical interpretation as the magnetic fields generated by small current loops.", "revisions": [ { "version": "v1", "updated": "2024-11-19T13:52:42.000Z" } ], "analyses": { "keywords": [ "calderón problem", "normal-to-tangential map encodes geometric information", "dimensional riemannian manifold", "total symbol determines", "beltrami field equation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }