English

Discriminants of convex curves are homeomorphic

dg-ga 2008-02-03 v1 Differential Geometry

Abstract

For a given real generic curve \ga:S1RPn\ga: S^1\to \Bbb {RP}^n let D\gaD_\ga denote the ruled hypersurface in RPn\Bbb {RP}^n consisting of all osculating subspaces to \ga\ga of codimension 2. A curve \ga:S1RPn\ga: S^1\to \Bbb {RP}^n is called convex if the total number of its intersection points (counted with multiplicities) with any hyperplane in RPn\Bbb {RP}^n does not exceed nn. In this short note we show that for any two convex real projective curves \ga1:S1RPn\ga_1:S^1\to\Bbb {RP}^n and \ga2:S1RPn\ga_2:S^1\to\Bbb {RP}^n the pairs (RPn,D\ga1)(\Bbb {RP}^n,D_{\ga_1}) and (RPn,D\ga2)(\Bbb {RP}^n,D_{\ga_2}) are homeomorphic answering a question posed by V.Arnold.

Keywords

Cite

@article{arxiv.dg-ga/9608007,
  title  = {Discriminants of convex curves are homeomorphic},
  author = {B. Shapiro},
  journal= {arXiv preprint arXiv:dg-ga/9608007},
  year   = {2008}
}

Comments

The usual AMSTeX file, 7 pages, no figures AMSTeX