How Big Can the Quantum World Be? Physicists Probe the Limits.

It’s a mere speck of matter — a piece of silica crystal no bigger than a virus, levitated in a light beam. But it is almost as motionless as the laws of physics permit. Two teams of researchers, in Austria and Switzerland, have independently succeeded in freezing such minuscule nanoparticles, just 100 to 140 nanometers across, almost entirely into their lowest-energy quantum state…

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