Induced CFJ Term in nonlocal Lorentz-Violating QED: Natural Regularization from Entire Dirac Operators
arXiv:2607.13858
The paper examines how the Carroll‑Field‑Jackiw term is radiatively generated in a Lorentz‑violating, nonlocal extension of quantum electrodynamics, showing that nonlocal form factors based on the Dirac operator naturally regularize the loop integrals and yield a finite coefficient.
Abstract
We investigate the radiative generation of the Carroll--Field--Jackiw (CFJ) term in nonlocal Lorentz- and CPT-violating extensions of quantum electrodynamics. Nonlocality is introduced through entire nonlocal form factors being functions of the Dirac operator in the fermionic sector. Using the derivative expansion of the one-loop fermionic determinant, we derive the induced CFJ contribution and analyze its ultraviolet (UV) behavior after Wick rotation. For one class of nonlocal form factors, loop integrals become naturally convergent, yielding a finite CFJ coefficient without the need for an external UV regulator. For a second class, the coefficient is rendered finite through an Abel regularization prescription. In both cases, the CFJ structure is preserved while its coefficient is continuously deformed by the ratio between the fermion mass and the nonlocality scale. Our results demonstrate that nonlocality provides a natural framework for controlling UV contributions to radiatively induced topological terms.
19 pages, 5 figures