On tangents to quadric surfaces
| dc.creator | Borcea, Ciprian | |
| dc.creator | Goaoc, Xavier | |
| dc.creator | Lazard, Sylvain | |
| dc.creator | Petitjean, Sylvain | |
| dc.date | 2004-02-24 | |
| dc.date.accessioned | 2026-07-07T05:05:42Z | |
| dc.date.available | 2026-07-07T05:05:42Z | |
| dc.description | We study the variety of common tangents for up to four quadric surfaces in projective three-space, with particular regard to configurations of four quadrics admitting a continuum of common tangents. We formulate geometrical conditions in the projective space defined by all complex quadric surfaces which express the fact that several quadrics are tangent along a curve to one and the same quadric of rank at least three, and called, for intuitive reasons: a basket. Lines in any ruling of the latter will be common tangents. These considerations are then restricted to spheres in Euclidean three-space, and result in a complete answer to the question over the reals: ``When do four spheres allow infinitely many common tangents?''. | |
| dc.description | 50 pages | |
| dc.identifier | https://arxiv.org/abs/math/0402394 | |
| dc.identifier | http://arxiv.org/abs/math/0402394 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/70263 | |
| dc.subject | Algebraic Geometry | |
| dc.subject | 14N05 (Primary) 14J28, 14P05 (Secondary) | |
| dc.title | On tangents to quadric surfaces | |
| dc.type | text |