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Werner Heisenberg

1901 - 1976

Werner Heisenberg, 1901 - 1976. German physicist and proponent of the Heisenberg Uncertainty Principle.

Werner Heisenberg was a German physicist, and a key member of the 'Copenhagen Interpretation', which proposed an observer-creation understanding of quantum phenomena, based on Niels Bohr's theories and Heisenberg's Uncertainty Principle.

  • Nationality
  • German

  • Subject
  • Physics, theoretical

  • Fields
  • Quantum Mechanics, Nuclear Physics

  • Distinctions
  • Nobel Prize (1932): Creation of Quantum Mechanics

  • Posts
  • Director of the Kaiser Wilhelm Institute for Physics, Berlin-Dahlem, and taught at the Berlin University, 1942-5.

    Director of the Max Planck Institute for Physics, Göttingen, 1946 - 1958.

    Director of the Max Planck Institute for Physics (now the Werner Heisenberg Institute), Munich, 1958 - 1970.

    President of the German Research Council

    Chairman of the Commission for Atomic Physics

    Chairman of the Nuclear Physics Working Group

    President of the Alexander von Humboldt Foundation

  • Publications
  • Über quantentheoretischer Umdeutung, 1925 (Quantum theoretical re-interpretation of kinematic and mechanical relations), Zeitschrift für Physik in September 1925.

    Three-part series of papers on the S-matrix, 1942-4.

  • Laws
  • Uncertainty Principle

    Heisenberg commutator: a law of multiplication which describes properties of atoms

  • Theories
  • Uncertainty Principle (1927)

    Hydrodynamics of turbulent flows

    Contributions to theories of atomic nucleus, subatomic particles, ferromagnetism, cosmic rays.

  • Equations
  • Uncertainty Principle: $σ_xσ_p ≥ {ℏ}/{2}$

    where $σ_x$ and $σ_p$ are examples complementary variables, the precision of one can be measured with inverse proportion to the precision of knowledge of the other. i.e. the precisely a particle's position is known the less precise can its momentum be known. The sigma symbol represents the standard deviation of the variables. $ℏ$ is the reduced Planck's constant, $ℏ = ℎ/{2π}$

No physicist has produced as much controversy regarding his or her involvement in politics as Werner Heisenberg. In the 1930s, many physicists, such as Einstein and Schrödinger, left Germany because of the nazi oppression, Heisenberg elected to remain in Germany. During the war, he took a research development post which on the surface seemed to be helping the Germans develop a nuclear weapon, which did not succeed.

Niels Bohr, Werner Heisenberg, and Wolfgang Pauli, ca. 1935
Niels Bohr, Werner Heisenberg, and Wolfgang Pauli, ca. 1935

In a famous incident, Heisenberg went to Copenhagen in September 1941, after the German invasion of Denmark. He met with his old mentor, Niels Bohr, and a private conversation they had on that occasion has been the source of much speculation. Bohr fled shortly afterwards to Britain, then the USA, where he helped the Americans develop the atomic bomb. Heisenberg returned to Germany and continued working on the German nuclear effort. Whether Heisenberg had sought Bohr's assistance in the development of the bomb is unknown for sure, but the two men's relationship thereafter was strained.

After the war, Heisenberg promoted nuclear power for Germany, and he worked on physics questions, such as the unified field theory of elementary particles.

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