API - 13: Random Walk of Photon in the Stellar Interior (Prof. Dr. Binil Aryal, TU / 20 May 2021)

Photons do not travel in a straight line, but rather collide with larger particles (actually gases on the way) and get redirected in a fashion. Photon walks randomly if the energy is transferred through radiative transport in the stellar interior. In this lecture, we discussed random walk of photon in a plain and find expression for total number of steps and hence the displacement. This expression can be used to calculate the time taken by the photon to reach the surface of the star.