Planck Discovers Quantum Law: Physics Reborn
Max Planck had spent years trying to explain why the energy distribution of black-body radiation didn't match classical physics predictions. On October 19, 1900, he presented his solution to the German Physical Society: energy is not emitted continuously but in discrete packets he called 'quanta,' each with energy proportional to its frequency. The equation E=hv introduced Planck's constant, one of the most fundamental numbers in physics. Planck himself was deeply uncomfortable with his own discovery, calling it 'an act of desperation.' He spent years trying to reconcile quanta with classical physics. Einstein, Bohr, Heisenberg, and Schrodinger ran with the idea instead, building quantum mechanics into the most successful physical theory ever devised. Planck received the Nobel Prize in Physics in 1918.
October 19, 1900
126 years ago
Key Figures & Places
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