Radiative generation of leptonic CP violation

Three CP-violating phases of the 3x3 lepton flavor mixing matrix V are entangled with one another in the renormalization-group evolution from the seesaw scale (Lambda(SS)similar to 10(14) GeV) to the electroweak scale (Lambda(EW)similar to 10(2) GeV). Concerning the Dirac phase delta, we show that delta=90 degrees at Lambda(EW) can be radiatively generated from delta=0 degrees at Lambda(SS) in the minimal supersymmetric standard model, if three neutrino masses are nearly degenerate. As for the Majorana phases rho and sigma, it is also possible to radiatively generate rho=90 degrees or sigma=90 degrees at Lambda(EW) from rho=0 degrees or sigma=0 degrees at Lambda(SS). The one-loop renormalization-group equations for the Jarlskog invariant and two off-diagonal asymmetries of V are derived, and their running behaviors from Lambda(SS) to Lambda(EW) are numerically illustrated.