1. The problem statement, all variables and given/known data Hi, I have a question regarding a set of equations in Feynmann volume 3. On chapter 11, page 11, Feynmann discusses the right-hand and left-hand circulation for the polarization of the photon. He states: "In the classical theory, right-hand circular polarization has equal components in x and y which are 90 out of phase. In the quantum theory, a right-hand circularly polarized (RHC) photon has equal amplitudes to be polarized |x> or |y>, and the amplitudes are 90 out of phase. Calling a RHC photon a state |R> and a LHC photon a state |L>, we can write: 2. Relevant equations |R> = (|x> + i|y>) / sqrt(2) |L> = -(|x> - i|y>) / sqrt(2)." 3. The attempt at a solution This is more of a question, but isn't it true that for RHC the x-component is 90 ahead rather than behind? Thus, shouldn't we place the i (which is a 90 phase factor) in front of the |x> instead of the |y>? Same question goes for the LHC equation, but with phases reversed. Thanks.