A German theoretical physicist who is regarded as the father of the
Quantum theory. He was the first person to propose that light and other
forms of electromagnetic radiation are emitted and absorbed from matter not
as waves, but as discrete packets of energy called quanta. Plank's name
lives on in Plank's constant, which related the energy of quantum to the
frequency of radiation. He was awarded the Nobel prize for physics in 1918
for his work in thermodynamics.