Planck, Max Karl Ernst Ludwig
The German Max Karl Ernst Ludwig Planck (1858 - 1947), son to a jurist, was a theoretical physicist.
He was an excelent lecturer on theoretical physics.
He derived Planck's law, which described the observed radiation spectrum emitted by a black-body. The central assumption was the Planck postulate, the supposition that electromagnetic energy E could be emitted only as a multiple of an elementary unit:
E = h×ν
where h = 6.62607015·10-34 J·Hz-1 is the Planck constant and ν the frequency of the radiation.
He lent his name to the Planck law, the Planck constant, and the Planck units:
Planck length = 1.616255(18)·10-35 m
Planck mass = 2.176434(24)·10-8 kg
Planck time = 5.391247(60)·10-44 s
Planck temperature = 1.416784(16)·1032 K
See also
Last modified:10 January 2026 2.51 p.m.