Radiation reaction. From classical physics to quantum fields

An enormous number of electrons are contained in plasma, and this paper discussed the 'handling of electrons themselves.' Experts say that the Dirac equation in quantum mechanics is the equation of electrons. However, after suggesting the Dirac equation, Dirac proposed one classical mechanics approach 'electronic model with light radiation,' namely 'classical equation of reaction of radiation.' This paper discussed that this reaction of radiation is strongly related to the state-of-the-art plasma science using 10 PW class laser. It described a single electron model that interacts with a high intensity electromagnetic field that cannot be seen with ordinary plasma science. The explanation items are as follows: (1) quantum electro-dynamics (QED): electromagnetic mechanics with vacuum fluctuation, (2) nonlinear Compton scattering in light radiation mechanism, (3) Brown motion as theory, and (4) reaction experiment of radiation at ELI-NP. In the experiment of (4), since Romania's ELI-NP has two 10 PW lasers as a sole country in the world and an electron beam LINAC of 720 MeV at the maximum, it is possible to lead the electron bunch from LINAC directly to the experimental area and make an interaction between laser and electron. Scattered electrons are measured with a calorimeter, and radiation light is measured with newly designed gamma ray measuring instrument to observe the final state of scattering particles. (A.O.)