A while ago I made a post asking why light diffracts and was directed to QED by Feynman. I have now read the book (or the relevant part at least) and it explains diffraction by the number of possible routes of photons through an aperture as being reduced when the is gap made smaller, and therefore the probability is equalled out less, meaning there is a more substantial chance of a photon arriving at a point other than directly through the gap, i.e. diffraction is observed. I understand that, but Feynman uses the simplification in the book of there being a finite number of paths, but in reality can’t a photon take an infinite number of routes, so regardless of the size of the aperture the paths should always be equalled out shouldn’t they?(adsbygoogle = window.adsbygoogle || []).push({});

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# Why light diffracts and was directed to QED by Feynman

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