. . . To encourage the growth of any science, the best thing we can do is to meet together in its interest, to discuss its problems, to criticize each other's work and, best of all, to provide means by which the better portion of it may be made known to the world. . . .
We show that for closed finite sized systems with an odd number of real fermionic modes, even in the presence of interactions, there are always at least two fermionic operators that commute with the Hamiltonian. There is a zero mode corresponding to the fermion parity operator as well as additional linearly independent zero modes, one of which is 1) the one that is continuously connected to the Majorana mode solution in the non-interacting limit, and 2) less prone to decoherence when the system is opened to contact with an infinite bath. We also discuss that the degree of robustness of Majorana qubits, which relies not so much on non-locality but instead on the fermionic gap, and the details of the environmental noise and the strength of static disorder.