A confluence of numerical and theoretical results leads us to conjecture that the Hilbert-Schmidt separability probabilities of the 15-and 9-dimensional convex sets of complex and real two-qubit states (representable by 4 × 4 density matrices ρ) are . We, now, set the
in the complexcase-conforming to a pattern we find, manifesting the Dyson indices (β = 1, 2, 4) of random matrix theory-we take S complex (ν) proportional to S 2 real (ν). We also investigate the real and complex qubit-qutrit cases. Now, there are two variables, ν 1 =