Photon in the Earth-ionosphere cavity: Schumann resonances

We study a quantum analogy of Schumann resonances by solving massless and massive spin-1 particle equations derived from the Zitterbewegung model in an annular cavity background with poorly conducting walls. We also show that the massless case and the massive case in the $m_0^2 \rightarrow 0$ limit are compatible with Maxwell's electromagnetic theory. Furthermore, from the massive case, we predict an upper limit for the mass of the photon of 1.3x$10^{-50}$kg. The bound on the mass of the photon is compatible with the current limit in the literature.