English

Convex Hull of Two Circles in R^3

Algebraic Geometry 2017-01-24 v2

Abstract

We describe convex hulls of the simplest compact space curves, reducible quartics consisting of two circles. When the circles do not meet in complex projective space, their algebraic boundary contains an irrational ruled surface of degree eight whose ruling forms a genus one curve. We classify which curves arise, classify the face lattices of the convex hulls, and determine which are spectrahedra. We also discuss an approach to these convex hulls using projective duality.

Keywords

Cite

@article{arxiv.1612.09382,
  title  = {Convex Hull of Two Circles in R^3},
  author = {Evan D. Nash and Ata Firat Pir and Frank Sottile and Li Ying},
  journal= {arXiv preprint arXiv:1612.09382},
  year   = {2017}
}

Comments

20 pages, many color .eps pictures