A quantum gas can be tied into knots using magnetic fields. Our researchers were the first to produce these knots as part of a collaboration between Aalto University and Amherst College, U.S., and they have now studied how the knots behave over time. The surprising result is that the knots untie themselves over a short period of time, before turning into a vortex.
Source:
https://phys.org/news/2019-10-quantum-untie.html