Hi all, According to quantum theory, for an electron vibrating in one dimension, only probability of position is meaningful. My question is will there be a e&m radiation by such a motion, if yes, how to appreciate it from the possibility argument, say, if only the probability at each position is the true description of such a motion, how come there comes up with a frequency of the motion. If no, will there be a radiation by an oscillating ion in one dimension? I find it very difficult to go from classical to quantum picture, anyone please help. Thank you very much.