EFFECTS OF HEAVY BOSONIC EXCITATIONS ON QED VACUUM
EFFECTS OF HEAVY BOSONIC EXCITATIONS ON QED VACUUM
We discuss the contribution of axion-like excitations (ALE) to the vacuum birefringence in the limit m A ≳ ω, where m A is the mass of the excitation and ω the energy of test photons interacting with an external (intense) magnetic field. The relevance of this term with respect to …