This paper presents a phenomenological extension of classical electrodynamics in which the vacuum is modeled as an emergent structured medium described by a scalar order parameter coupled to electromagnetic fields. The framework preserves gauge invariance while predicting experimentally testable effects including temperature-dependent vacuum birefringence, modified electromagnetic propagation, and delayed resonant electromagnetic emission. The model is formulated as an effective field theory intended to explore possible mesoscopic vacuum dynamics beyond standard electrodynamics.
Erick Sangalang (2026) studied this question.