Scientists link diamonds by quantum entaglement

A pair of diamond crystals big enough for the eye to see has been linked by quantum entanglement. This means that a vibration in the crystals could not be meaningfully assigned to one or other of them: both crystals were simultaneously vibrating and not vibrating.

Quantum entanglement — interdependence of quantum states between particles not in physical contact — has been well established between quantum particles such as atoms at ultra-cold temperatures. But like most quantum effects, it doesn’t tend to survive either at room temperature or in objects large enough to see with the naked eye.

A team led by Ian Walmsley, a physicist at the University of Oxford, UK, found a way to overcome both those limitations, demonstrating that the weird consequences of quantum theory apply at large scales as well as at very small ones. The work is published today in Science.