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arXiv · 1904.02732

Solving the Gap Equation of the NJL Model through Iteration: Unexpected Chaos

Angelo Martínez·Alfredo Raya
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Abstract

We explore the behavior of the iterative procedure to obtain the solution to the gap equation of the Nambu-Jona-Lasinio (NLJ) model for arbitrarily large values of the coupling constant and in the presence of a magnetic field and a thermal bath. We find that the iterative procedure shows a different behavior depending on the regularization scheme used. It is stable and very accurate when a hard cut-off is employed. Nevertheless, for the Paul-Villars and proper time regularization schemes, there exists a value of the coupling constant (different in each case) from where the procedure becomes chaotic and does not converge any longer.

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Angelo Martínez, Alfredo Raya. 2019-04-04. Solving the Gap Equation of the NJL Model through Iteration: Unexpected Chaos. https://doi.org/10.3390/sym11040492

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