Polynomial codegrees and dual defects of skew-symmetric determinantal loci

Let AD(2n2)m2s,2nAD^{2s,2n}_{\binom{2n}{2}-m} denote the skew-symmetric determinantal locus in even dimension with the indicated rank parameter. For any fixed m>0m>0, the even skew-symmetric determinantal-locus conjecture.

the dual defect of AD(2n2)m2s,2n is max(0,(2n2)m), independently of n,and the codegree of AD(2n2)m2s,2n depends polynomially on n.\begin{aligned} &\text{the dual defect of }AD^{2s,2n}_{\binom{2n}{2}-m}\text{ is }\max\left(0,\binom{2n}{2}-m\right),\text{ independently of }n,\\ &\text{and the codegree of }AD^{2s,2n}_{\binom{2n}{2}-m}\text{ depends polynomially on }n. \end{aligned}

The conjecture is motivated by the known case m=1m=1, whose codegree is polynomial in nn and whose dual defect is (2s2)1\binom{2s}{2}-1. The source also suggests an analogous statement in odd dimensions, but does not formulate it as a separate conjecture; no resolution is given.

Sources & referencesView supporting material

Primary source

Laurent Manivel, Mateusz Michałek, Leonid Monin, Tim Seynnaeve and Martin Vodička, “Complete quadrics: Schubert calculus for Gaussian models and semidefinite programming”, arXiv:2011.08791 (2020).

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.