Conservation of knottiness in real and idalized fluids
Conservation of knottiness in real and idalized fluids
This is a joint talk with PACM/MAE. 听听To tie a shoelace into a knot is a relatively simple affair. Tying a knot in a field is a different story, because the whole of space must be filled in a way that matches the knot being tied at the core. The possibility of such localized knottedness in a space-filling field has fascinated physicists and mathematicians ever since Kelvin鈥檚 'vortex atom' hypothesis, in which the atoms of the periodic table were hypothesized to correspond to closed vortex loops of different knot types. 听More recently,听knottiness (Helicity) has re-emerged as a 听conserved quantity in manyidealized situations (such as Euler fluids and ideal plasmas). By presenting experiments, simulations and analytical work, I will talk about how this topological quantity can be more or less conserved than you might have expected in light, fluids and superfluids