### HMC Physics Colloquium

Tuesdays at 16:30 in Shanahan Center for Teaching and Learning, Room B460

## Alexander Sushkov

Yale University

Why Does the Universe Have More Matter than Anti-matter? A Search for Violation of Parity and Time-reversal Symmetries

Feb. 2, 2010

Last year’s Nobel Prize in physics was awarded to Nambu, Kobayashi, and Maskawa for their study of nature’s broken discrete symmetries (charge conjugation C, parity P, and time reversal T). However, what we know about the breaking of these symmetries is not enough to explain the apparent matter-antimatter asymmetry of the universe. One of the ways to study the breaking of parity and time reversal symmetries is to search for the permanent electric dipole moment (EDM) of the electron. I will describe an experimental search for this EDM, based on a solid paramagnetic ferroelectric $$\mathrm{Eu_{0.5} Ba_{0.5} Ti O_3}$$. We expect a preliminary improvement of the current EDM limit by a factor of 10, with the sensitivity gain originating from large densities $$n = 10^{22}~\mathrm{cm^{-3}}$$, and from large effective electric fields $$E$$ = 10 MV/cm, due to the ferroelectric displacement of the ions in the crystal lattice field.