Experimental data describing the diffusion action of chemical waves support the old theoretical proposal that the concept of quantum mechanics could be derived classically from the diffusion of self-organized waves of Brownian particles. Therefore, photons are here treated as classical Brownian particles, and their properties are discussed from that point of view. The observed microwave background radiation is interpreted as secondary photons emanating from solar (primary) photons, and termed as the solar microwave background radiation (SMBR). The Hubble-Nernst (photon-decay) constant is calculated from the known experimental values of the SMBR energy density and the solar irradiance at 1 AU as 2.395 x 10-18 ? 0.03 kg kg-1 s-1 (or 73.90 ? 0.8 km Mpc-1 s-1 in velocity units). The temporal patterns in the COBE FIRAS data sets confirm the predicted dependence of the SMBR energy density on the distance from the Sun ? the inverse-square law. Plaskett?s red-shift analysis of the solar surface is used to evaluate both the amplitude (T = 3.1 ? 0.2 mK) and the direction (α = 167o? 2o; δ = - 1o? 3o) of the observed SMBR dipole. The existence of solar granulation, super-granulation, giant cells, pores, sunspots and groups of sunspots, may explain the observed temperature fluctuations of the observed microwave background radiation at different angular resolutions. The limits of these fluctuations are determined from the temperature fluctuations of granules, super-granules, and giant cells. These coincidences may lead to the conclusion that the observed microwave background radiation could be considered as a fingerprint of the solar photosphere.
