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arXiv · hep-ph/9511231

Computing numerically the functional derivative of an effective action

J. Baacke·A. Suerig
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Abstract

The functional derivative of the effective action with respect to an external field is part of the equation of motion of this field if one-loop effects induced by quantum fluctuations or thermal fluctuations are included when minimizing the action of this field. Examples occur in all field theories displaying classical solutions or - as in the Nambu-Jona-Lasinio model - self consistent field configurations. We describe here a numerical method for computing such functional derivatives; we use a fermion field with Yukawa interaction to an external field as an example which is sufficiently simple and sufficiently general. We compare the computed functional derivative to analytical estimates.

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J. Baacke, A. Suerig. 1995-11-03. Computing numerically the functional derivative of an effective action. https://arxiv.org/abs/hep-ph/9511231

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