Mechanical systems all tangled up

The motion of two ion pairs is linked through “spooky action at a distance”

Researchers have linked the vibrations of two separated atom pairs, catching sight of a strange quantum effect called entanglement in a system that approaches the scale of everyday life. This new link between two pairs of oscillating ions, reported in the June 4 Nature, “pushes the bounds on where entanglement can be seen,” says study coauthor John Jost of the National Institute of Standards and Technology’s campus in Boulder, Colo.