Colloquium Calendar

A pre-eminent problem of modern physics is to reconcile the disparity between the laws of quantum physics – which apply at the small scale – and the laws of gravity – that apply at the large scale. This talk will motivate the nature of the fundamental problem and highlight some of the ideas we are currently pursuing to address it. In particular, a decisive confrontation of gravity and quantum theory calls for mechanical objects, massive enough to measurably gravitate with each other, prepared in quantum states of their motion.

Optical atomic clocks now reach fractional frequency uncertainties below 10^-18, pressing toward a redefinition of the second. Optical lattice clocks harness laser cooling and trapping technologies for holding and probing ultracold atoms. These clocks are based on simple atomic spectroscopy, but as we continue zooming in to narrower frequency ranges, we encounter challenges that test our fundamental understanding of how atom-light and atom-atom interactions work, demanding cutting-edge laser stabilization and quantum state control.

We have all heard the saying “If you cannot measure it, you cannot make it,” for optical fabrication, but it applies to most things where precision is required. The past decades have seen fantastic advancements in optical systems from astronomical telescopes that see to the edge of the universe to virtual reality systems that enable people to experience worlds that never exist. The new optical components and systems have required new ways to measure them.