The S-Matrix Is the Oracle Physicists Turn To in Times of Crisis

In 1943, the German physicist Werner Heisenberg distracted himself from World War II by pondering a crisis in quantum theory. Predictions about how particles should behave were occasionally giving nonsensical, infinite results. These infinities led Heisenberg to distrust the way quantum physics was depicting reality, and to expect that a revolutionary new theory would eventually overthrow particle…

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