Neutron Electric Dipole Moment in the Standard Model: Complete Three-Loop Calculation of the Valence Quark Contributions

Abstract

We present a complete three-loop calculation of the electric dipole moment of the $u$ and $d$ quarks in the standard model. For the $d$ quark, more relevant for the experimentally important neutron electric dipole moment, we find cancellations which lead to an order of magnitude suppression compared with previous estimates.