Induced Lorentz-Violating Chern-Simons Term in QED and Anomalous Contributions to Effective Action Expansions

Abstract

I present a unified formulation of anomalous contributions in quantum field theories by calculating directly the effective action using the background field and covariant-derivative expansion technique. I use this method to determine uniquely the induced Chern-Simons term from the a Lorentz and CPT violating term in fermion QED Lagrangian. The outstanding ambiguity is resolved by properly taken into account the noncommutivity of $A$ and $\partial$. The resulting vacuum polarization tensor acquires a non-Feynman diagram anomalous contribution which accounts for the discrepancy between the present calculation and the other calculations.

8 pages

Cited by in corpus (4)

• Lorentz-CPT violation, radiative corrections and finite temperature
• Constraint from Lamb Shift and Anomalous Magnetic Moment on Radiatively Induced Lorentz and CPT Violation in Quantum Electrodynamics
• The structure of radiatively induced Lorentz and CPT violation in QED at finite temperature
• A Note on the Radiatively Induced Lorentz and CPT Violated Chern-Simons-like Term in the Extended Quantum Electrodynamics