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arXiv · 1402.4988

Form factors and non-local Multiplicative Anomaly for fermions with background torsion

Guilherme de Berredo-Peixoto·Alan E. Maicá
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Abstract

We analyse the Multiplicative Anomaly (MA) in the case of quantized massive fermions coupled to a background torsion. The one-loop Effective Action (EA) can be expressed in terms of the logarithm of determinant of the appropriate first-order differential operator acting in the spinors space. Simple algebraic manipulations on determinants must be used in order to apply properly the Schwinger-DeWitt technique, or even the covariant perturbation theory (Barvinsky and Vilkovisky, 1990), which is used in the present work. By this method, we calculate the finite non-local quantum corrections, and analyse explicitly the breakdown of those algebraic manipulations on determinants, called by MA. This feature comes from the finite non-local EA, but does not affect the results in the UV limit, in particular the beta-functions. Similar results was also obtained in previous papers but for different external fields (QED and scalar field).

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Guilherme de Berredo-Peixoto, Alan E. Maicá. 2014-02-20. Form factors and non-local Multiplicative Anomaly for fermions with background torsion. https://doi.org/10.1088/0264-9381/31/12/125002

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