In my undergraduate days I remember learning about the double slit experiment etc. in quantum mechanics. And I'm only now starting to learn about the Standard model. So there are these fields; higgs, electro-magnetic, strong and weak nuclear. So if a photon is a perturbation in the electro-magnetic field, and it sort of bounces around traveling in accordance with probability. Then take a photon that is a much longer wavelength than visible light, like a radio signal, well I'm in my car, you're in your car, and we're both listening to the same radio station, well we're both hearing the same song. Does that mean that the same photon we're listening bounced around both our antennas, or the tower projecting the radiation output many distinct photons? So in which case the theoretical maximum people that can listen to the radio station is the number of electrons in the station antenna which were jostling about?