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Restoration of broken symmetries in Self-Consistent RPA

A. Rabhi·P. Schuck·R. Bennaceur·G. Chanfray·J. Dukelsky
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Abstract

It is shown that the Self-Consistent RPA (SCRPA) approach allows in a very natural way to restore symmetries, spontaneously broken on the mean field level. This is achieved via the introduction of a second Lagrange multiplier which constrains the variance of the symmetry operator to zero. This important feature of SCRPA, here pointed out for the first time, is illustrated employing a simplified model of the nuclear superfluidity.

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A. Rabhi, P. Schuck, R. Bennaceur, G. Chanfray, J. Dukelsky. 2001-06-28. Restoration of broken symmetries in Self-Consistent RPA. https://arxiv.org/abs/nucl-th/0106064

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