How to unsnarl a tangle of threads, according to physics

Physicists may have found a solution for the rage-inducing tangles that crop up in everything from electronics cords to necklaces: to free a single thread from a tangle of many, you must shake it not too fast and not too slow but with just the right frequency. Ishant Tiwari at the Georgia Institute of Technology in Atlanta and his colleagues created a vibrating robot to determine how to best jiggle a single thread from such a tangle. Human cells have a resonant frequency – and it's just barely audible