The Standard Model cannot explain the dominance of matter over anti-matter in our universe, which
indicates the existence of undiscovered time-reversal (T) symmetry violation. Proposed particle physics
theories predict new particles that violate T-symmetry, which generically induce an electric dipole
moment in the electron (eEDM). I will present the most precise measurement of the eEDM to date
using electrons confined inside molecular ions, subject to a huge intra-molecular electric field, and
evolving coherently for up to three seconds. Our result is consistent with zero and improves on the
previous upper bound of the eEDM by a factor of ∼ 2.4. Our sensitivity to 10 −19 eV shifts in molecular
ions provides constraints on broad classes of new physics at energies an order of magnitude beyond the
direct reach of the Large Hadron Collider.