# Does a photon observe other photons moving past it at the speed of light?

*They say that the speed of light is the same for all inertial observers, but what if the observer is a particular photon within a laser beam? Each photon in a laser beam would see all the other photons passing it at speed c, therefore the laser beam would instantly break up. How do you solve this conundrum?*

The answer is that a photon can't count as an observer. Time slows down for objects that move at close to the speed of light. For an object moving *at* the speed of light, time would grind to a halt. So how fast you clock something moving past you if you can't measure time turns out to be a nonsensical question.

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