Vladimir S. Malinovsky

Heat an ordinary quartz watch by ten degrees, and it will start losing seconds each day. Atomic clocks are more precise, but they take up an entire cabinet. Diamond with a tiny defect, a nitrogen vacancy, promises atomic-clock accuracy in the volume of a grain of sand.

A pendulum swings both left and right at the same time. In the atomic world, such a 'double' state is called a Schrödinger's cat: a particle exists in two states simultaneously, like the cat in the thought experiment — both alive and dead. Scientists have found a way to assemble such states from many atoms using short light pulses.