Real-point conjecture for separating extreme rays of nonnegative ternary and quaternary quartics

Let P3,6P_{3,6} and P4,4P_{4,4} denote the cones of nonnegative homogeneous polynomials of the indicated degrees in three and four variables, respectively, and let Σ3,6\Sigma_{3,6} and Σ4,4\Sigma_{4,4} denote the corresponding sums-of-squares cones. For a polynomial outside the relevant sums-of-squares cone, a separating extreme ray is understood in the sense of the cited theorem.

Real-point conjecture. For pP3,6Σ3,6p \in P_{3,6} \setminus \Sigma_{3,6} there exist v1,,v9R3v_1,\ldots,v_9 \in \mathbb{R}^3 yielding a separating extreme ray for pp. Analogously, for pP4,4Σ4,4p \in P_{4,4} \setminus \Sigma_{4,4}, there exist v1,,v8R4v_1,\ldots,v_8 \in \mathbb{R}^4 yielding a separating extreme ray for pp.

This conjecture strengthens Blekherman's conjecture by requiring the points describing the relevant extreme rays to be real. The paper presents it as a formulation based on its results; its resolution is not specified in the supplied text.

Sources & referencesView supporting material

Primary source

Sadik Iliman and Timo de Wolff, “Separating inequalities for nonnegative polynomials that are not sums of squares”, arXiv:1201.4061 (2012).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.