Here you see the good folks on QI shooting smoke rings across the room. Why does a donut-shaped cloud come out of a circular opening? Why are smokers able to blow smoke rings, even when they’re not ...

A vortex ring is a torus-shaped, fluidic region where the fluid spins around an imaginary axis line. Vortex rings exist almost ubiquitously in nature 1,2,3,4 and have stimulated numerous studies for ...

Chern-Simons theory is a topological quantum field theory set in three dimensions that has profoundly influenced our understanding of gauge theories and topology. Its formulation, which emphasises ...