Precision Lepton and Lepton Flavor Violation

The MOLLER experiment at Jefferson Lab is a next-generation parity-violating electron scattering (PVES) experiment designed to precisely measure the weak charge of the electron via Møller scattering. This will be achieved by measuring the parity-violating asymmetry, A_PV, in the scattering of longitudinally polarized electrons off unpolarized electrons, providing the most accurate determination of the weak mixing angle, sin²θ_W, at low momentum transfer (Q²). With a remarkable precision of 0.8 parts per billion (ppb) in measuring A_PV, the MOLLER experiment will achieve a fractional accuracy of 0.1% in sin²θ_W, matching the precision obtained from Z-pole measurements. This precise determination of sin²θ_W will allow MOLLER to probe for potential new physics beyond the Standard Model, with sensitivity to neutral current interactions as small as 10^-3·G_F, and access to new physics mass scales up to 7.5 TeV. Benefiting from Jefferson Lab's high-luminosity, high-energy electron beam and leveraging expertise from previous parity-violation experiments, MOLLER provides a unique opportunity to push the boundaries of our understanding of fundamental interactions. The experiment is now in its construction phase, with installation in Hall A targeted for 2025. This talk will outline the scientific goals, describe the experimental apparatus, and provide the latest updates on the construction progress.