Analyticity in Hubbard Models
نویسنده
چکیده
Abstract. The Hubbard model describes a lattice system of quantum particles with local (on-site) interactions. Its free energy is analytic when βt is small, or βt/U is small; here, β is the inverse temperature, U the on-site repulsion and t the hopping coefficient. For more general models with Hamiltonian H = V +T where V involves local terms only, the free energy is analytic when β‖T ‖ is small, irrespectively of V . There exists a unique Gibbs state showing exponential decay of spatial correlations. These properties are rigorously established in this paper.
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