High Quality Content by WIKIPEDIA articles! The Hubbard model is an approximate model used, especially in solid state physics, to describe the transition between conducting and insulating systems. The Hubbard model, named after John Hubbard, is the simplest model of interacting particles in a lattice, with only two terms in the Hamiltonian (see example below): a kinetic term allowing for tunneling (`hopping`) of particles between sites of the lattice and a potential term consisting of an on-site interaction. The particles can either be fermions, as in Hubbard`s original work, or bosons, when the model is referred to as either the `Bose–Hubbard model` or the `boson Hubbard model`.