Schematic representation of the case n = 3. (a) The solutions of equations (6) and (7) lie on the circle given by the intersection of the sphere of radius R (here represented for the pure state with R = 1) and the plane π passing through the points A, B and C. The dashed triangle ABC, lying on the plane π, has all sides equal to . The inner circle is inscribed into the triangle. (b) View of the plane π with the circumscribed and inscribed circles of radii r_e and r_i, which correspond, respectively, to values R = 1 and . The thin red circle is an intermediate case where positive and negative probabilities coexist (the latter lie outside the triangle). (c) Circular cone with apex at the origin O and basis circle of radius r_i. The height k of the cone is the distance between the origin and the plane π.