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When reading about the Double Slit Experiment, often the author will rave about something like 'the photon must pass through both slits at the same time'.

I'm struggling a bit with the simple phrasing of this statement, and can't come to terms with two questions I have:

- Isn't the fact that a photon is traveling at the speed of light means that time doesn't pass within its inertial frame? That is, all of its motion is on the space axis of spacetime? As such wouldn't it be very possible for the photon to travel through both slits? By way of analogy, if I would be in a room where there are 2 open doors on one wall, and for me, within the room, time wouldn't pass, I can quite easily go through 1 door, then back, then through the other. For someone outside the room, where time does pass, it will appear as if I 'passed through both doors at the same time' - but I could only have done so because time didn't pass within my inertial frame?
- Also, what does the double slit screen looks like - in terms of size in space - to the photon? Isn't the fact that it travels at the speed of light means that space outside its inertial frame shrinks to infinitely small dimension? And so the photon does not see the double slits as two spaced apart slits but rather as two slits in the same space? Saying 'it passed through both slits' needs the addition 'because they were, from the photon point of view, at the same point in space'?

As probably obvious, there are child-like questions that don't show deep understanding of concepts like spacetime, so please forgive me for what might be a complete mess of misunderstanding.

Thanks,

Izhaki

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# The Double Slit Experiment from a Photon Point of View

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