The convex hull of a space curve 
Kristian Ranestad (University of Oslo)

The boundary of the convex hull of a compact algebraic curve in real 3-space defines a real algebraic surface. For general curves, that boundary surface is reducible, consisting of tritangent planes and a scroll of stationary bisecants. In recent work with Sturmfels we extend classical formulas to express the degree of this surface in terms of the degree, genus and singularities of the curve.  For rational curves we present methods for computing their defining polynomials, and exhibit a range of examples.

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