# Felix Bloch

Felix Bloch ( born October 23, 1905 in Zurich, † September 10, 1983 ) was a Swiss- American physicist of Jewish origin. He received the 1952 Nobel Prize in Physics.

## Life and work

Between 1924 and 1927, Bloch studied at the ETH Zurich mathematics and physics. He then continued his studies in Leipzig with Werner Heisenberg. The topic of his thesis was the Schrödinger equation. The doctoral thesis dealt with the behavior of electrons in crystal lattices and was the starting point for his life's work: the quantum mechanical treatment of solid state physics to its foundations he contributed many as the band model of electrons in solids and the Bloch function.

1929 Bloch was an assistant with Wolfgang Pauli at the ETH Zurich. After several intermediate positions, he became in 1931 assistant to Werner Heisenberg in Leipzig. After the seizure of power by the Nazis, he fled back to Switzerland and in 1934 at Stanford University, where he remained until 1971. He took over as first the chair of theoretical physics. In 1939 he became an American citizen.

During the Second World War, Bloch worked in the Manhattan Project at the implosion bomb at Los Alamos, but left the project before its completion, reportedly due to differences with Oppenheimer. Then it reach important work for ferromagnetism, and the measurement of the magnetic moments of nuclei. In 1946 he discovered independently by Edward Mills Purcell and together with William Webster Hansen, and Martin Packard nuclear magnetic resonance (english Nuclear Magnetic Resonance, NMR), which is used to represent the composition and structure of solids and liquids and chemical compounds. In 1952 Bloch together with Edward Mills Purcell for this discovery the Nobel Prize for physics.

Bloch was 1954-1955 Director General of CERN in Geneva.

The following physical properties bear his name:

- Bethe -Bloch formula
- Bloch function
- Bloch equations
- Bloch sphere
- Bloch vector
- Bloch- wall
- Bloch electron

From Bloch and Nordsieck Arnold comes also the solution of the infrared problem in quantum electrodynamics.