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Do shadows weigh anything? And do they affect the weight of objects they are cast over?
Ron Dippold
San Diego, California, US
Shadows weigh nothing but can have apparent negative weight.
Consider what a shadow is: it is the lack of photons (light) bouncing off an area relative to the lit areas around it. Photons have no rest mass, but they do have energy – as encapsulated in the equation E = mc2. A stream of photons delivers a force in the direction of travel when it bounces off a surface, as does a stream of water hitting an object.…
