Neutron Electric Dipole Moment on the Lattice

Abstract

For the neutron to have an electric dipole moment (EDM), the theory of nature must have T, or equivalently CP, violation. Neutron EDM is a very good probe of novel CP violation in beyond the standard model physics. To leverage the connection between measured neutron EDM and novel mechanism of CP violation, one requires the calculation of matrix elements for CP violating operators, for which lattice QCD provides a first principle method. In this paper, we review the status of recent lattice QCD calculations of the contributions of the QCD $\Theta$-term, the quark EDM term, and the quark chromo-EDM term to the neutron EDM.Comment: Plenary talk presented at the 35th International Symposium on Lattice Field Theory (Lattice 2017), Granada, Spain, June 2017. 15 pages, 10 figure