When a black body is heated, electromagnetic radiation is emitted with a spectrum corresponding to the temperature of the body, and not to its composition. Calculating the form of the spectrum using then-known physical laws gave an unreasonable result; the radiation in the high-frequency area of the spectrum became infinite. Max Planck solved this problem in 1900 by introducing the theory of "quanta", that is, that radiation consists of quanta with specific energies determined by a new fundamental constant, thereafter called Planck's constant.