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Algebraic equivalence between certain models for superfluid--insulator transition

Luigi Amico
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Abstract

Algebraic contraction is proposed to realize mappings between models Hamiltonians. This transformation contracts the algebra of the degrees of freedom underlying the Hamiltonian. The rigorous mapping between the anisotropic $XXZ$ Heisenberg model, the Quantum Phase Model, and the Bose Hubbard Model is established as the contractions of the algebra $u(2)$ underlying the dynamics of the $XXZ$ Heisenberg model.

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Luigi Amico. 2000-12-12. Algebraic equivalence between certain models for superfluid--insulator transition. https://doi.org/10.1142/s0217984900000963

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