Planck's revolutionary discovery, one of the most influential in all of science, was that energy emitted by a resonator could on have discrete values or quanta. The energy for a resonator of frequency '''''ν''''' is '''''hν''''', where "'''''h'''''" is a universal constant that is now called Planck's constant. This theory explained discrepancies between theory and observations, and became known as quantum theory. This helped lay a foundation for the future discovery of quantum mechanics.
Planck was award the [[Nobel
prize]] for physics in 1918.<ref>The Earth and Its Peoples A Global History, Bulliet et al, 2005</ref>
Planck's son was executed in 1945 for attempting unsuccessfully to assassinate [[Adolf Hitler|Hitler]] in 1944.