High Energy Physics Seminar

Nearly forty years ago, Caves, Thorne, and their collaborators asked a simple question: what are the limits to the detection of a small change in the position of an object? Based on their conceptual work, in 2016, LIGO achieved the first direct detection of a passing gravitational wave. If one is looking for a rapid impulse delivered to a device instead of a quasi-periodic wave signal, one can ask about the analogous quantum limits to detectability. I will discuss some work on this ``quantum impulse metrology'' problem, and present applications in the search for dark matter. In particular, I will present a concept for an optomechanical detection scheme which, near the limits of what is possible according to quantum mechanics, would be capable of direct detection of sufficiently heavy dark matter candidates purely through their gravitational interactions with the device.