Max Planck -

): He introduced this fundamental constant of nature, which has a value of approximately , to define the relationship between energy and frequency.

He developed the Planckian distribution law, which accurately describes the spectrum of electromagnetic radiation emitted by a black body in thermal equilibrium, fitting experimental data across all wavelengths. Max Planck

While attempting to solve the "ultraviolet catastrophe" (the failure of classical physics to predict black-body radiation at high frequencies), Planck proposed that energy oscillators in a cavity could only change energy in discrete increments ( ), not continuously. Planck’s Constant ( ): He introduced this fundamental constant of nature,

He served as president of the Kaiser Wilhelm Society (1930–1937), which was renamed the Max Planck Society in 1948. which has a value of approximately