From Few-To Many- Body Quantum Physics and Back
Quantum systems consisting of a small number of particles, such as those encountered in atomic and molecular physics, can be described by the Schr\”odinger equation. For large numbers of identical particles, such as the electrons in a condensed matter system, the quantum field point of view is often more productive. Fascinating new properties of matter have been explained or discovered by regarding the quantum field as the fundamental description. In particular, the excitations of the quantum field can typically be described by quasi-particles, particle-like objects with properties distinct from those of the original particles. I will review old and new results in mathematical physics that describe and exploit this particle structure in order to understand physical phenomena, including recent results regarding topologically ordered phases of matter.
(Tea served in First Floor Commons Room at 3:30pm.)