elliptope

English

Etymology

coined in: M. Laurent and S. Poljak, On a positive semidefinite relaxation of the cut polytope, Linear Algebra Appl., 223/224, (1995), 439-461

Noun

elliptope (plural elliptopes)

1. (mathematics) The set of all real, square symmetric matrices whose diagonal entries are all equal to one and whose eigenvalues are all non-negative.
   • 2016, Anupam Prakash, Jamie Sikora, Antonios Varvitsiotis, Zhaohui Wei, “Completely positive semidefinite rank”, in arXiv‎^[1]:

     In particular, we use a known lower bound on the size of matrix representations of extremal quantum correlations which we apply to high-rank extreme points of the $n$-dimensional elliptope. Lastly, we study cpsd-graphs, i.e., graphs $G$ with the property that every doubly nonnegative matrix whose support is given by $G$ is cpsd.