This just popped into my head earlier tonight, for whatever reason. Imagine a photon, a lone photon, that was the only thing in existence. According to relativity theory, am I correct to say that without any other object by which it may be said to be in motion relative to, we cannot say that the photon is in motion? However, due to relativity, the photon would experience no passage of time, a phenomenon that is attributed to its velocity of c. It seems paradoxical to say that an object that is not in motion has a velocity, yet this seems to be what is happening here. Can anyone clarify exactly what is going on here for me?