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arXiv · 0709.2904

Dynamical Lorentz and CPT symmetry breaking in a 4D four-fermion model

M. Gomes·T. Mariz·J. R. Nascimento·A. J. da Silva
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Abstract

In a 4D chiral Thirring model we analyse the possibility that radiative corrections may produce spontaneous breaking of Lorentz and CPT symmetry. By studying the effective potential, we verified that the chiral current $\barψγ^μ γ_5 ψ$ may assume a nonzero vacuum expectation value which triggers the Lorentz and CPT violations. Furthermore, by making fluctuations on the minimum of the potential we dynamically induce a bumblebee like model containing a Chern-Simons term.

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M. Gomes, T. Mariz, J. R. Nascimento, A. J. da Silva. 2008-03-27. Dynamical Lorentz and CPT symmetry breaking in a 4D four-fermion model. https://doi.org/10.1103/physrevd.77.105002

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