A Reinterpretation of Stimulated Emission as Spontaneous Emission Under Non Thermodynamic Equilibrium Conditions

In 1916, Einstein postulated the existence of induced emission (einstrahlung), where a quantum of radiation from a light beam induced a molecule in an excited state to emit a quantum of radiation of the same frequency. The stimulating photon was unchanged by the ghostly interaction and the net effect of induced emission, which is now commonly known as stimulated emission, was indistinguishable from spontaneous emission (ausstrahlung). Here I show that the existence of stimulated emission, postulated by Einstein, is an artifact of his use of the Boltzmann distribution for continuous energy states. Here I show that with the use of Planck’s distribution for discontinuous energy states, stimulated emission becomes superfluous. By using the quantum-theoretical distribution, it becomes clear that at thermodynamic equilibrium, the emission of all quanta of radiation are indistinguishable from the spontaneous emission of quanta. When molecules where the lower energy state and excited states are in thermodynamic equilibrium are subject to an intense light composed of radiation quanta of the appropriate frequency, the molecules enter a non-equilibrium state. In the non-equilibrium state, the population of energy states becomes inverted such that there are more excited states than lower energy states. Such a distribution is thermodynamically equivalent to a negative temperature state. In response to the incident light, the molecules spontaneously emit radiation quanta with the same frequency as the incident quanta. The transformation between incident radiant energy and emitted radiant energy is a consequence of the first and second laws of thermodynamics. There is no need to postulate a photon that induces the response, unchanged by the interaction.