Viscous Photons

It's quite clear why this might happen. To exist is to have a gap between what you are and how you appear, a gap that can't be located anywhere "on" you. This must apply to a photon, if a photon is real. A photon can't just be a "massless particle" that can't interact with other photons. That assertion just seems like a mathematical convenience. One simply had to cool down a system sufficiently to allow for its little photonic contradictoriness to reveal itself. And have sufficient imagination to expect to see that.