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Radiatively Induced Lorentz and CPT Violation in Schwinger Constant Field Approximation

M. Chaichian·W. F. Chen·R. Gonzalez Felipe
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Abstract

The Schwinger proper-time method is an effective calculation method, explicitly gauge invariant and nonperturbative. We make use of this method to investigate the radiatively induced Lorentz and CPT-violating effects in quantum electrodynamics when an axial vector interaction term is introduced in the fermionic sector. The induced Lorentz and CPT-violating Chern-Simons term coincides with the one obtained using a covariant derivative expansion but differs from the result usually obtained in other regularization schemes. A possible ambiguity in the approach is also discussed.

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M. Chaichian, W. F. Chen, R. Gonzalez Felipe. 2000-12-15. Radiatively Induced Lorentz and CPT Violation in Schwinger Constant Field Approximation. https://doi.org/10.1016/s0370-2693(01)00196-4

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