How small a box can you confine a photon to before its mass is large enough to form a black hole?(adsbygoogle = window.adsbygoogle || []).push({});

I think you can make an estimate on the momentum (and therefore the energy) based on the size of the box using the Uncertainty Principle - knowing the energy gives you the mass via E=mc^2, but how do you figure out the mass and size needed to form the black hole?

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# Confining a photon to form a black hole

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