Classical and quantum reconciliation of electromagnetic radiation: vector Unruh modes and zero-Rindler-energy photons

A great deal of evidence has been mounting over the years showing a deep connection between acceleration, radiation, and the Unruh effect. Indeed, the fact that the Unruh effect can be codified in the Larmor radiation emitted by the charge was used to propose an experiment to experimentally confirm the existence of the Unruh thermal bath. However, such connection has two puzzling issues: (1) how the quantum Unruh effect can be codified in the classical Larmor radiation and (2) the fundamental role played by zero-Rindler-energy modes of the Unruh thermal bath in such a context. Here we generalize a recent analysis made for the scalar case to the more realistic case of Maxwell electrodynamics and settle these two puzzling issues.