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arXiv · 1302.2375

Radiative generation of the CPT-even gauge term of the SME from a dimension-five nonminimal coupling term

R. Casana·M. M. Ferreira Jr·R. V. Maluf·F. E. P. dos Santos
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Abstract

In this letter we show for the first time that the usual CPT-even gauge term of the standard model extension (SME) can be radiatively generated, in a gauge invariant level, in the context of a modified QED endowed with a dimension-five nonminimal coupling term recently proposed in the literature. As a consequence, the existing upper bounds on the coefficients of the tensor $(K_{F}) $ can be used improve the bounds on the magnitude of the nonminimal coupling, $λ(K_{F}),$ by the factors $10^{5}$ or $10^{25}.$ The nonminimal coupling also generates higher-order derivative contributions to the gauge field effective action quadratic terms.

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R. Casana, M. M. Ferreira Jr, R. V. Maluf, F. E. P. dos Santos. 2013-09-07. Radiative generation of the CPT-even gauge term of the SME from a dimension-five nonminimal coupling term. https://doi.org/10.1016/j.physletb.2013.09.010

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