2011 OPERA faster-than-light neutrino anomaly

In 2011, the Oscillation Project with Emulsion-tRacking Apparatus (OPERA) experiment mistakenly observed neutrinos appearing to travel faster than light. Even before the source of the error was discovered, the result was considered anomalous because speeds higher than that of light in vacuum are generally thought to violate special relativity, a cornerstone of the modern understanding of physics for over a century.

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