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Generalized Crossover in multiparameter Hamiltonians

Pietro Parruccini·Paolo Rossi
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Abstract

Many systems near criticality can be described by Hamiltonians involving several relevant couplings and possessing many nontrivial fixed points. A simple and physically appealing characterization of the crossover lines and surfaces connecting different nontrivial fixed points is presented. Generalized crossover is related to the vanishing of the RG function $Z_t^{-1}$. An explicit example is discussed in detail based on the tetragonal GLW Hamiltonian.

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Pietro Parruccini, Paolo Rossi. 2001-07-09. Generalized Crossover in multiparameter Hamiltonians. https://doi.org/10.1103/physreve.64.047104

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