One-loop electron mass and three-loop Dirac neutrino masses

In the context of a left-right extension of the standard model of quarks and leptons with the addition of a gauged U(1)(D) dark symmetry, it is shown how the electron may obtain a radiative mass in one loop and two Dirac neutrinos obtain masses in three loops. (c) 2021 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).