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Physics

Bell Inequalities

Quick fact

John Bell derived his famous inequality in 1964, but it took nearly two decades before experimental violations were conclusively observed, earning the 2022 Nobel Prize in Physics for Aspect, Clauser, and Zeilinger.

Why this is interesting

Imagine two dice that always show opposite numbers, no matter how far apart they are—could they be secretly coordinated? This gut feeling is what Bell inequalities challenge, revealing a weirdness at the heart of reality.