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Quantum fluctuations of chiral condensate in the analytically regularized Nambu--Jona-Lasinio model

V. E. Rochev
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Abstract

The problem of quantum fluctuations of the chiral condensate due to next-to-leading contributions is investigated. Meson contributions to the chiral condensate are calculated in the Nambu--Jona-Lasinio model with the analytical (dimensional) regularization in a framework of the mean-field expansion. The pion contribution can be significant, while the sigma-meson contribution is small in the regime of physical values of the model parameters. Non-pole contributions are also estimated and found to be small.

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V. E. Rochev. 2003-11-29. Quantum fluctuations of chiral condensate in the analytically regularized Nambu--Jona-Lasinio model. https://arxiv.org/abs/hep-ph/0312004

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