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New functional representation for Hubbard model, coherent state and tower of algebras

V. M. Zharkov
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Abstract

New functional representation for the strongly interacting systems is proposed which contains a new type of the quantum coherent state. As a result the new algebraic structure- so called "tower of algebras" appears which gives the tower (or hierarchy) of models. Generalization of Gutzwiller approximation in theory of metal-insulator phase transition is obtained. It is shown that the deformation parameters may be relevant to the order parameters in the physics of strongly correlated systems.

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V. M. Zharkov. 1996-12-03. New functional representation for Hubbard model, coherent state and tower of algebras. https://arxiv.org/abs/cond-mat/9612033

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