This version 2 doesn’t conclude definitely on the non reality of the Doppler Effect for photons since there are some poins to clarify. Why is that? Because there are still phenomenons, like Doppler broadening in particular, which needs more works to look at before attributing it or not to the Doppler Effect. Even if there are still some doubts, however, we show strong arguments against the reality of the Doppler Effect for photons. Also, most of the text of the version 1 is conserved, with additional elements and some corrections. Abstract This idea of the non Doppler Effect for a light photon has been promoted by Rongqing Dai’s thought experiment (i). This thought experiment is expressed by this question: can it be true that the photon energy can “randomly increase or decrease everywhere at anytime”? This energy dilemma for a photon is created when a moving vessel A emit a photon which can be measured by a vessel B having a relative velocity with respect to the source A. The Doppler Effect says that the measured frequency in B will be different from the one emitted in A. Since the photon energy is proportional to the frequency, according to Planck’s formula, then, there is no conservation of energy and energy is lost or created solely because there is a relative velocity between the source and the observer (which relative velocity can be unknown by each vessels)! It can be worse than that, since if we put reflectors on both vessels, until the photon is emitted by the source A, then the photon will go back and forth between the two vessels, with the energy of the photon increasing at each reflection and going to infinity if the two vessels are approaching. This is quite impossible! Then, Rongqing Dai thought experiment leads to a more general questioning about the validity of the energy conservation law, the Planck energy formula and the reality of the Doppler Effect for photons. This anomaly of the energy in the life of a photon could be explained by the sole fact that there can’t be any Doppler Effect for a reflected light photon since photons can’t possess an infinity of frequencies! Indeed, since matter is quantized and can absorb only frequencies which are adaptated to their quantic level of energy, then, there would be an infinity of lost photons in the universe if the Doppler Effect for photons were real! i An Energy Dilemma Created When Quantum Physics Started. December 2025. Rongqing Dai. DOI:10.13140/RG.2.2.15188.26249/4. LicenseCC BY 4.0.
Didier Viel (Thu,) studied this question.