Instantaneously? https://physics.stackexchange.com/questions/613005/how-long-does-it-take-an-electron-to-emit-or-absorb-a-photon https://physics.stackexchange.c

Instantaneously? https://physics.stackexchange.com/questions/613005/how-long-does-it-take-an-electron-to-emit-or-absorb-a-photon https://physics.stackexchange.com/questions/613005/how-long-... says it takes time for a photon to be absorbed and then reemitted