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Why does shadows reflection got these blurry edges , is it something related to quantum physics , how photon travels to make these outlines look like this? shadow

Does the uncertainty principle plays role in cast of shadows , and is there 100% perfect shadow (even from a small source of light) ?


marked as duplicate by John Rennie, Norbert Schuch, ZeroTheHero, Jon Custer, sammy gerbil Mar 15 '17 at 2:23

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I am assuming the shadow in your picture was produced in sunlight. The blur at the edges is mostly due to the fact that the light source, the sun, is not a point source but rather an extended object so that near edge of the shadow your hand is blocking light from part of the sun but not all of the sun.

Quantum physics can be used to explain the diffraction of light as it passes by an edge but that is not the effect you are seeing here.


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