Max Karl Ernst Ludwig Planck (1858 - 1947) a German physicist who is considered to be the inventor of quantum theory.
Born on April 23, 1858 in Kiel, Planck started his physics studies at München university in 1874, graduating in 1879 in Berlin. He returned to München in 1880 to teach at the university, and moved to Kiel in 1885. There he married Marie Merck in 1886. In 1889, he moved to Berlin, where from 1892 on he held the chair of theoretical physics.
In 1899, he discovered a new fundamental constant, which is named Planck's constant, and is, for example, used to calculate the energy of a photon. One year later, he discovered the law of heat radiation, which is named Planck's Law of Radiation. This law became the basis of quantum theory, which emerged ten years later in cooperation with Albert Einstein and Niels Bohr.
From 1905 to 1909, Planck acted as the head of the Deutsche Physikalische Gesellschaft (German Physical Society). His wife died in 1909, and only one year later he married Marga von Hoesslin. In 1913, he became head of Berlin university. For the foundation of quantum physics, he was awarded the 1918 Nobel Prize in Physics. From 1930 to 1937, Planck was head of the Kaiser-Wilhelm-Gesellschaft zur Förderung der Wissenschaften (KWG).
During World War II, Planck tried to convince Hitler to spare Jewish scientists. Planck's son Erwin was executed on July 20, 1944, for treason in connection with an attempted assassination of Hitler. After Max Planck's death on October 4, 1947 in Göttingen, the KWG was renamed as the Max-Planck-Gesellschaft zur Förderung der Wissenschaften (MPG).