3 ms·

> from the point of view of the photon the moment of it's emission and detection are the same. It's traveling at the speed of light... From the perspective of

• jcims 9y ago
  I've been wondering this lately. Does the photon actually exist in the space between where it is emitted and where it is absorbed? In other words, if nothing interacts with it along the way, is it really there?
  • simonh 9y ago
    That's really the riddle of the Schroedinger equation for any quantum entity.
  • gowld 9y ago
    That's metaphysics. Physically, there's no way to answer the question. See also: https://en.wikipedia.org/wiki/Virtual_particle https://en.wikipedia.org/wiki/Virtual_particle
  • btilly 9y ago
    The answer is a curious no. More precisely, the double slit experiment demonstrates that the possibility that it existed in one place at a particular point in time interacts with the possibility that it existed elsewhere, and the interaction affects where it can be possibly found.
• pdonis 9y ago
  > From the perspective of the photon (really kind of silly since the photon can't have any mass, and therefore no observer), there is no time or distance traveled. It takes 0 time to travel 0 distance. This is not correct. It is not possible to have an inertial frame in which the photon is at rest. It is possible to construct coordinate charts in which the photon's worldline has constant values for all but one coordinate; but that coordinate is not a "time" coordinate, and there is no well-defined notion of "time" or "distance" along the photon's worldline in such coordinates.