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When I began learning about optical interference, I came to know about destructive interference in which light waves cancel each other.
How the energy is still conserved ?
I found that the conservation is not disturbed and the photon emission is stopped instantaneously. How can the electron know what to do, whether to return to ground state giving back energy in the form of photons or to undergo other phenomenon like electron scattering...
Consider two laser sources emitting laser undergo perfect destructive interference after a distance d by means of a mirror. Then the light from both the laser goes uninterfered up to distance d. How can the energy be conserved?