History of Quanta

Abstract

Retrospectively, we owe the origin of quantum physics primarily to the investigation of the spectral distribution of the radiation emitted by heated bodies. This distribution could not be described with formulas derived from classical physical treatments. But in 1900 Max Planck (1858–1947) was able to derive the correct law for the black body radiation by the assumption that the energy within the radiation is “quantized”. This assumption can be treated as the beginning of quantum physics. As the radiation emitted by a “black” body takes a special place in understanding and introducing the quantum ideas in optics, we shall analyze it in more detail after some introducing remarks.