Planck, Max (mäks plängk), 1858–1947, German physicist. Seeking to explain the experimental spectrum spectrum, arrangement or display of light or other form of radiation separated according to wavelength, frequency, energy, or some other property. Beams of charged particles can be separated into a spectrum according to mass in a mass spectrometer (see mass
..... Click the link for more information. (distribution of electromagnetic energy according to wavelength) of black body black body, in physics, an ideal black substance that absorbs all and reflects none of the radiant energy falling on it. Lampblack, or powdered carbon, which reflects less than 2% of the radiation falling on it, approximates an ideal black body.
..... Click the link for more information. radiation, he introduced the hypothesis (1900) that oscillating atoms absorb and emit energy only in discrete bundles (called quanta) instead of continuously, as assumed in classical physics. The success of his work and subsequent developments by Albert Einstein, Niels Bohr, Werner Heisenberg, Erwin Schrödinger, and others established the revolutionary quantum theory quantum theory, modern physical theory concerned with the emission and absorption of energy by matter and with the motion of material particles; the quantum theory and the theory of relativity together form the theoretical basis of modern physics.
..... Click the link for more information. of modern physics, of which Planck is justly regarded as the father. In 1918, Planck received the Nobel Prize in physics for his work on black body radiation. He was professor at the Univ. of Berlin (1889–1928) and president (1930–35) of the Kaiser Wilhelm Society for the Advancement of Science, Berlin, which after World War II was reconstituted as part of the Max Planck Institutes. He was an editor of the Annalen der Physik and member of the Royal Society (London) and the American Physical Society. His name is honored in Planck's constant Planck's constant (plängks), fundamental constant of the quantum theory . It is represented by the letter h and has a value of 6.
..... Click the link for more information. . English translations of his works include A Survey of Physics (1925, new ed. 1960), Introduction to Theoretical Physics (5 vol., 1932–33), Treatise on Thermodynamics (3d rev. ed. 1945), and Scientific Autobiography and Other Papers (1949).

Planck, Max (Karl Ernst Ludwig)

(born April 23, 1858, Kiel, Schleswig—died Oct. 4, 1947, Göttingen, W.Ger.) German physicist. He studied at the Universities of Munich and Kiel, then became professor of theoretical physics at the University of Berlin (1889–1928). His work on the second law of thermodynamics and blackbody radiation led him to formulate the revolutionary quantum theory of radiation, for which he received a Nobel Prize in 1918. He also discovered the quantum of action, now known as Planck's constant, h. He championed Albert Einstein's special theory of relativity, but he opposed the indeterministic, statistical worldview introduced by Niels Bohr, Max Born, and Werner Heisenberg after the advent of quantum mechanics. As the influential president of the Kaiser Wilhelm Society (later the Max Planck Society) until his resignation in 1937, he appealed to Adolf Hitler to reverse his devastating racial policies. His son was later implicated in the July Plot against Hitler and was executed.