Title: Tying Knots in a Quantum Fluid (Video)
Abstract: Knots are familiar entities that appear at a captivating nexus of art, technology, mathematics,and science. Following a lengthy period of theoretical investigation and development, they have recently attracted great experimental interest in contexts ranging from knotted DNA and nanostructures to vortex knots in classical fluids. In this talk I will discuss the first controlled creation and detection of knot solitons in a quantum fluid, a spinor Bose-Einstein condensate. Our observations establish an experimental foundation for future studies of the stability, dynamics, applications, of knot solitons within quantum systems. The knot solitons themselves provide a striking experimental demonstration of the celebrated Hopf fibration, which unites many seemingly unrelated physical phenomena.