Max Karl Ernst Ludwig Planck
1858-1947
Max Karl Ernst Ludwig Planck
1858-1947
Ph.D. at the University of Munich, 1879. Instructor at Munich, associate professor at the University of Kiel, 1885-89, then Professor of Theoretical Physics at Berlin, 1889-1928. Received the Nobel Prize in 1918 for discovering the energy quantum. President of the Kaiser Wilhelm Society for the Advancement of Science, now the Max Planck Society, 1930-35.
Worked on the increase of entropy, phase transitions and changes in state (work anticipated by Gibbs), black body radiation in an electromagnetic approach independent of the details of the radiating material, and the connection between entropy and probability theory.
Constructed the Planck distribution for black body radiation, 1900, and derived the distribution on the basis on the quantum hypothesis that the energies of the radiating oscillators were quantized. Introduced the Planck constant h and the Boltzmann constant k, wrote Boltzmann's relation between the entropy and statistical weights in the modern form S = k lnW for the first time. Planck later considered philosophical questions in physics and was a statesman of science.