C. W. Sandbo Chang

Physicists have for the first time created a trio of photons entangled as a single whole, not just pairwise. To achieve this, a special chip was cooled to a temperature hundreds of times lower than that of deep space — any noise threatened to destroy the fragile link.

A whisper in a noisy room is nearly indistinguishable. A conventional amplifier adds its own noise and drowns out the weak sound. A quantum amplifier works differently: it amplifies the signal while adding almost no extra noise, like a perfect ear. But even such an ear has its own problems.