K. Birgitta Whaley, University of California-Berkeley

Topic: "Macroscopic Quantum Superposition States ---- Ideality and Reality"  (Video)

Abstract: What are macroscopic quantum superposition states, do they exist, and if not, why not? These questions have fascinated quantum physicists and chemists since the days of Schrodinger and his cat. The extreme superposition expressed by Schrödinger's cat epitomizes such states and current experiments seek to realize "cat states" made from larger and larger numbers of particles in a variety of physical systems. Studying such states tell us a lot about the nature and power of quantum mechanics, e.g., for large scale quantum information processing. Yet what do we really mean by the "size" or "Schrödinger cattiness" of a quantum superposition in a strongly interacting quantum system composed of large numbers of elementary particles? I shall discuss our current understanding of such quantum mechanical superposition states, their significance for quantum mechanics as well as experimental advances in generating and manipulating them.