author keywords: Entanglement; Separability; Multipartite system; Low-rank approximation; Nonlinear eigenvalue problem; Nonlinear singular value problem

TL;DR: This paper concerns the approximation over a multipartite system whose subsystems consist of symmetric rank-1 matrices that are entangled via the Kronecker tensor product, except that the discussion in this paper is limited to real-valued matrices. (via Semantic Scholar)