Mass gain and loss of non-relativistic electrons in photon-electron interactions

It is shown that the electrons gain mass as their non-relativistic velocities increase. This process is realized by the absorption of photons in the colliding process. In an inverse manner, they loss their mass when they radiate photons. The related equations are derived by using the relativistic mass equation and independently by considering the non-relativistic energy relation. The Compton scattering and photon emission phenomena are revisited with the new theory.