Max Planck

Max Planck was a German theoretical physicist who is regarded as the founder of quantum theory. His work on the radiation of black bodies introduced the concept of the quantum and transformed the understanding of matter and of energy.

Early Life and Education

Planck was born in 1858 in Kiel, Germany, to a family of lawyers and theologians. He studied at the universities of Munich and Berlin.

He was advised against the study of physics, which was thought to be nearly complete. He nevertheless pursued the subject and took a doctorate in 1879.

He worked as a lecturer and then as a professor at the University of Berlin. He was a member of the Prussian Academy of Sciences.

The Quantum Theory

Planck investigated the radiation emitted by a black body. He found that the classical theory could not explain the observed spectrum.

He proposed that the energy of the radiation is emitted in discrete packets, which he called quanta. The hypothesis was a radical departure from the classical physics.

The constant that relates the energy of a quantum to its frequency is known as the Planck constant. It is one of the fundamental constants of nature.

The Reception of the Theory

The theory was initially resisted and was confirmed by the work of Einstein on the photoelectric effect. The quantum theory was developed by Bohr, Heisenberg, and Schrödinger.

Planck was awarded the Nobel Prize in Physics in 1918. The award recognised his contribution to the development of the quantum theory.

He continued to work on the foundations of the theory. He sought to reconcile the quantum with the classical physics.

The Later Career

Planck was the president of the Kaiser Wilhelm Society, the predecessor of the Max Planck Society. He was a central figure in the German scientific establishment.

He remained in Germany during the Nazi period and tried to protect the scientific institutions. He was critical of the regime and was removed from his position.

His son Erwin was involved in a plot against Hitler and was executed. The loss affected him deeply, and he died in 1947 in Göttingen.

The Philosophy

Planck wrote on the philosophy of science and on the nature of physical reality. He argued for the reality of the physical world and against positivism.

He was a supporter of the theory of relativity and of the quantum theory. He was a member of the scientific community that transformed physics.

He was also a musician and a mountaineer. He was interested in the relation between science and religion.

The Legacy

Planck is regarded as one of the founders of modern physics. The quantum theory that he initiated is a foundation of the physical sciences.

The Max Planck Society is one of the leading research organisations in the world. It is named in his honour.

He is remembered for his insight and for his courage. His work continues to influence the development of physics.

The Black-Body Radiation

Planck investigated the radiation emitted by a black body. The classical theory could not explain the observed spectrum.

He proposed that the energy is emitted in discrete packets. The hypothesis introduced the quantum.

The constant that relates the energy to the frequency is known as the Planck constant. It is a fundamental constant of nature.

The Nobel Prize and the Recognition

Planck received the Nobel Prize in Physics in 1918. The award recognised his contribution to the quantum theory.

He was elected to the Prussian Academy of Sciences and to many other societies. He was a central figure in the German scientific establishment.

He was the president of the Kaiser Wilhelm Society. The society was renamed the Max Planck Society in his honour.

The Later Years

Planck remained in Germany during the Nazi period. He tried to protect the scientific institutions and was removed from his position.

His son Erwin was executed for his part in a plot against Hitler. The loss affected him deeply.

He died in 1947 in Göttingen. His work continues to influence the development of physics.

The Quantum Theory

Planck proposed the quantum hypothesis in 1900. The idea was a radical departure from the classical physics.

He was at first reluctant to accept the implications of his own theory. He tried for years to reconcile it with the classical framework.

The theory was developed by Einstein and by Bohr. It became the foundation of the modern physics.

The Early Life and the Career

Planck was born in Kiel in 1858. He studied at Munich and at Berlin and was a pupil of Helmholtz and of Kirchhoff.

He became a professor at Berlin and a member of the Prussian Academy. He was one of the most influential physicists of his time.

He was the editor of the Annalen der Physik. The journal published the work of Einstein and of other leading scientists.

See also

• Quantum theory
• Planck constant