Slave boson
The Slave Boson method is a method for dealing with models of strongly correlated systems. It is mainly used as an approximation for the Anderson impurity model in the limit that the Coulombic repulsion tends to infinity. However, it has been used for Hubbard models, such as in the theory of the high-Tc superconductors
It involves coupling the fermion operators to a boson field such that
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