Energy is not continuous but comes in discrete packets called quanta. The energy [latex]E[/latex] of a single quantum of electromagnetic radiation (a photon) is directly proportional to its frequency [latex]\nu[/latex]. This relationship is defined by the Planck-Einstein relation, [latex]E = h\nu[/latex], where [latex]h[/latex] is the プランク定数この概念は、古典物理学に根本的な挑戦を突きつけた。

















