Max Planck Born: The Reluctant Father of Quantum Physics

Max Planck didn't want to overturn physics. He was trying to solve an embarrassing mathematical problem in 1900: why the equations describing radiation from a heated object broke down at high frequencies, a failure known as the ultraviolet catastrophe. Born on April 23, 1858, in Kiel, Germany, into a family of scholars and ministers, he studied physics at the Universities of Munich and Berlin under some of the most distinguished scientists of the era. He was advised against studying physics because the field was considered essentially complete. He studied it anyway. His career was steady and productive but unremarkable until December 14, 1900, when he presented a paper to the German Physical Society proposing that energy was emitted not in continuous waves but in discrete packets, which he called "quanta." He called it a "lucky guess" and "an act of desperation," a mathematical trick to make the equations work. He spent years trying to reconcile the quantum hypothesis with classical physics, hoping to prove that the discontinuity was only apparent. It was not. The quantum revolution he accidentally started became the most successful physical theory ever formulated, explaining everything from the behavior of atoms to the functioning of semiconductors and lasers. Einstein used Planck's quantum hypothesis to explain the photoelectric effect in 1905, and Bohr used it to model the atom in 1913. Planck received the Nobel Prize in Physics in 1918. His personal life was marked by extraordinary tragedy. His first wife died in 1909. His eldest son was killed in World War I. His twin daughters both died in childbirth. His second son, Erwin, was executed by the Nazis in 1945 for his involvement in the July 20 plot to assassinate Hitler. Planck died on October 4, 1947, at age 89.