According to Maxwell's equations, an accelerating electron emits light. My question is, does Maxwell's equations explain the emission of all electromagnetic waves in the universe including, say, light emitted from a bulb?
Is this view of light emission from Maxwell's equations any different from the emission of EM waves when an electron makes a jump from a higher to a lower energy state in an atom?
Electromagnetism – Light from Maxwell’s Equations
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Best Answer
When we say that an accelerating electron emits light we are considering an electron as a classical particle, whereas when we talk about an electron jumping between the states in an atom, we are considering electron as a quantum particle. Thus, it would be incorrect to treat this as two different mechanisms of emission.
If we consider an atom in classical terms, it becomes clear why we need quantum mechanical description: an electron on an orbit is always accelerated, so it would emit light, lose its energy and eventually falls into the nucleus. Since this does not happen, classical description is unsatisfactory.
On the other hand, an accelerating electron can always be viewed quantum mechanically, as making transitions between states in a continuous spectrum. Thus, the quantum mechanical description is consistent with the Maxwell equations.