Wonders of Quantum Physics

The conclusion of the theory behind the wild question 'What is light made of?' is as follows:When a beam of light passes through a narrow gap, it spreads out, which is called diffraction.Diffraction can only be explained using waves. If light was acting like a particle, the light particles in the beam would either not get through the gap (if they were too big) or just pass straight through and the beam would remain unchanged.

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