by Aram W. Harrow, Anand Natarajan, Xiaodi Wu
Available on the arXiv as arXiv:1506.08834 and published as Commun. Math. Phys. Vol. 352, No. 3, pp 881-904 (2017)
Abstract
We present a stronger version of the Doherty–Parrilo–Spedalieri (DPS) hierarchy of approximations for the set of separable states. Unlike DPS, our hierarchy converges exactly at a finite number of rounds for any fixed input dimension. This yields an algorithm for separability testing that is singly exponential in dimension and polylogarithmic in accuracy. Our analysis makes use of tools from algebraic geometry, but our algorithm is elementary and differs from DPS only by one simple additional collection of constraints.