- Computational Neuroscience
I am interested in applications of atomic physics techniques to fundamental questions about the workings of the Universe. We are presently conducting two experiments to test symmetries of physical laws. In one experiment we are searching for a permanent electric dipole moment of 129Xe atoms, which can only exist if time-reversal symmetry, as well as CP symmetry, are violated. While CP symmetry is violated at a small level in the Standard Model, this violation is insufficient to explain the asymmetry between matter and anti-matter in the Universe. Our experiment is particularly sensitive to new sources of CP violation beyond the Standard Model. In another experiment we are searching for evidence of violation of Lorentz symmetry and CPT symmetry. While these symmetries are on a firm ground within a conventional field theory, they can be violated in more general theories including quantum gravity. Thus, CPT and Lorentz symmetry violations are some of the very few experimentally accessible signatures of quantum gravity effects.
Our experiments are typically performed by a small group of people and use a variety of experimental techniques and devices, such as optical pumping, NMR, high-Tc SQUID magnetometers, single frequency and high power diode lasers, multi-layer magnetic shields, ultra-low noise electronics, etc. Substantial effort is also devoted to detailed understanding and modeling of various systematic effects. We are also exploring practical applications of the precision atomic physics techniques. Recently we developed a very sensitive atomic magnetometer that can surpass even low-temperature SQUID detectors in magnetic field sensitivity. In collaboration with Princeton Center for Brain, Mind and Behavior we are developing its applications for imaging of the magnetic fields produced by the brain.