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arXiv · hep-ph/9907274

No Spontaneous Breakdown of Chiral Symmetry in Nambu-Jona-Lasinio Model

H. Kleinert·B. Van den Bossche
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Abstract

We argue that the spontaneous breakdown of symmetry in the chirally symmetric Nambu--Jona-Lasinio model which was supposed to illustrate the origin of the low mass of pions in hadron physics does not occur due to strong fluctuations in the sigma - pi field space. Although quarks acquire a constituent mass, sigma and pi turn out to have equal heavy masses of the order of the constituent quark mass.

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H. Kleinert, B. Van den Bossche. 2000-02-11. No Spontaneous Breakdown of Chiral Symmetry in Nambu-Jona-Lasinio Model. https://doi.org/10.1016/s0370-2693(00)00056-3

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