  consisting of five three-outcome tests pasted together in a loop. This test space is by no means pathological; it is both ortho-coherent and algebraic, and its logic is an orthomodular lattice. Moreover, it admits a separating set of dispersion-free states and hence, a classical interpretation. It can also be embedded in the test space \(\mathcal{A}_{\mathbf{H}}\) of any 3-dimensional Hilbert space \(\mathbf{H}\). Now consider how we might model a compound system consisting of two separated sub-systems each modeled by \(\mathcal{A}_5\). We would need to construct a test space \(\mathcal{B}\) and a mapping \(\otimes : X \times X \rightarrow Y = \cup \mathcal{B}\) satisfying, minimally, the following;