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Physics

Casimir Force

Quick fact

The Casimir force is so strong at sub-micrometer distances that it can cause tiny components in microelectromechanical systems (MEMS) to stick together, a problem engineers call 'stiction'.

Why this is interesting

Imagine two uncharged metal plates placed nanometers apart in a perfect vacuum – they should feel nothing, yet they mysteriously attract each other. What invisible hand pulls them together?