Max Planck (1858-1947) was a great German physicists. He advanced the subjects of thermodynamics, thermoelectricity, and the theory of dilute solutions, and was one of the founders of quantum mechanics.
Planck's revolutionary discovery, one of the most influential in all of science, was that a resonator could emit energy in discrete units, or quanta. The energy emitted by a resonator of frequency ν is hν, where "h" is a universal constant that is now called Planck's constant. This explanation resolved important discrepancies between theory and observations, and helped lay a foundation for the development of quantum mechanics.
Planck's son was executed in 1945 for attempting unsuccessfully to assassinate Hitler in 1944.
- The Earth and Its Peoples A Global History, Bulliet et al, 2005