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Self-consistent random phase approximation in the Schutte-Da-Providencia fermion-boson model

A. Rabhi
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Abstract

Self-consistent random phase approximation (SCRPA) is applied to the exactly solvable model with fermion boson coupling proposed by Schütte and Da-Providencia. Very encouraging results in comparison with the exact solution of the model for various observables are obtained. The transition from the normal phase to the phase with a spontaneously broken symmetry is carefully investigated. The strong reduction of the variance in SCRPA vs HF is pointed out.

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A. Rabhi. 2003-11-06. Self-consistent random phase approximation in the Schutte-Da-Providencia fermion-boson model. https://doi.org/10.1103/physrevc.69.017306

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