Science & technology | Particle physics

A second possible break in the laws of physics has been noted

This time it involves misbehaving muons

A magnetic moment

“WHO ORDERED that?” This was the reaction, famous in particle-physics circles, of Isidor Isaac Rabi to the discovery of the muon. Rabi, a Nobel laureate who helped America develop the atom bomb, was reflecting physicists’ general surprise that muons, which are, to all intents and purposes, just heavy and unstable versions of electrons, actually exist. To an orderly physicist’s mind they somehow seemed superfluous to Nature’s requirements.

This article appeared in the Science & technology section of the print edition under the headline “Model misbehaviour”

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