MAXENT APPROACH TO QUBITS

Abstract

We consider the Hubbard-like Hamiltonian used in Physica B 352 (2004) 269-279, using the MaxEnt approach and a CSCO, as the set of relevant operators which, obviously, close a partial Lie algebra with the Hamiltonian. So, it is possible to define a positive definite metric on the space spanned by the mean values of the CSCO. Particularly, the selected operators represent the occupation number, the aligned and antialigned pairs per site, respectively. The interesting question to be examined here is whether the above mentioned Hamiltonian have the property that the expectation values of a suitable operator are indeed zero and one (or a constant) qubits, and zero and +1 and -1, i.e., qutrits.