Felix Bloch
Encyclopedia
Felix Bloch was a Swiss
physicist
, working mainly in the U.S.
, Switzerland to Jewish parents Gustav and Agnes Bloch. He was educated there and at the Eidgenössische Technische Hochschule
, also in Zürich. Initially studying engineering he soon changed to physics
. During this time he attended lectures and seminars given by Peter Debye
and Hermann Weyl
at ETH Zürich and Erwin Schrödinger
at the neighboring University of Zürich
. A fellow student in these seminars was John von Neumann
. Graduating in 1927 he continued his physics studies at the University of Leipzig
with Werner Heisenberg
, gaining his doctorate in 1928. His doctoral thesis established the quantum theory of solids, using Bloch wave
s to describe the electrons.
He remained in European academia, studying with Wolfgang Pauli
in Zürich, Niels Bohr
in Copenhagen
and Enrico Fermi
in Rome before he went back to Leipzig assuming a position as privatdozent (lecturer). In 1933, immediately after Hitler came to power, he left Germany, emigrating to work at Stanford University
in 1934. In the fall of 1938, Bloch began working with the University of California at Berkeley 37" cyclotron to determine the magnetic moment of the neutron. Bloch went on to become the first professor for theoretical physics at Stanford. In 1939, he became a naturalized citizen of the United States. During WW II
he worked on nuclear power
at Los Alamos National Laboratory
, before resigning to join the radar
project at Harvard University
.
After the war he concentrated on investigations into nuclear induction and nuclear magnetic resonance
, which are the underlying principles of MRI
. In 1946 he proposed the Bloch equations
which determine the time evolution of nuclear magnetization. He and Edward Mills Purcell
were awarded the 1952 Nobel Prize
for "their development of new ways and methods for nuclear magnetic precision measurements." In 1954–1955, he served for one year as the first Director-General of CERN
. In 1961, he was made Max Stein Professor of Physics at Stanford University
.
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
, working mainly in the U.S.
Life and work
Bloch was born in ZürichZürich
Zurich is the largest city in Switzerland and the capital of the canton of Zurich. It is located in central Switzerland at the northwestern tip of Lake Zurich...
, Switzerland to Jewish parents Gustav and Agnes Bloch. He was educated there and at the Eidgenössische Technische Hochschule
ETH Zurich
The Swiss Federal Institute of Technology Zurich or ETH Zürich is an engineering, science, technology, mathematics and management university in the City of Zurich, Switzerland....
, also in Zürich. Initially studying engineering he soon changed to physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
. During this time he attended lectures and seminars given by Peter Debye
Peter Debye
Peter Joseph William Debye FRS was a Dutch physicist and physical chemist, and Nobel laureate in Chemistry.-Early life:...
and Hermann Weyl
Hermann Weyl
Hermann Klaus Hugo Weyl was a German mathematician and theoretical physicist. Although much of his working life was spent in Zürich, Switzerland and then Princeton, he is associated with the University of Göttingen tradition of mathematics, represented by David Hilbert and Hermann Minkowski.His...
at ETH Zürich and Erwin Schrödinger
Erwin Schrödinger
Erwin Rudolf Josef Alexander Schrödinger was an Austrian physicist and theoretical biologist who was one of the fathers of quantum mechanics, and is famed for a number of important contributions to physics, especially the Schrödinger equation, for which he received the Nobel Prize in Physics in 1933...
at the neighboring University of Zürich
University of Zurich
The University of Zurich , located in the city of Zurich, is the largest university in Switzerland, with over 25,000 students. It was founded in 1833 from the existing colleges of theology, law, medicine and a new faculty of philosophy....
. A fellow student in these seminars was John von Neumann
John von Neumann
John von Neumann was a Hungarian-American mathematician and polymath who made major contributions to a vast number of fields, including set theory, functional analysis, quantum mechanics, ergodic theory, geometry, fluid dynamics, economics and game theory, computer science, numerical analysis,...
. Graduating in 1927 he continued his physics studies at the University of Leipzig
University of Leipzig
The University of Leipzig , located in Leipzig in the Free State of Saxony, Germany, is one of the oldest universities in the world and the second-oldest university in Germany...
with Werner Heisenberg
Werner Heisenberg
Werner Karl Heisenberg was a German theoretical physicist who made foundational contributions to quantum mechanics and is best known for asserting the uncertainty principle of quantum theory...
, gaining his doctorate in 1928. His doctoral thesis established the quantum theory of solids, using Bloch wave
Bloch wave
A Bloch wave or Bloch state, named after Felix Bloch, is the wavefunction of a particle placed in a periodic potential...
s to describe the electrons.
He remained in European academia, studying with Wolfgang Pauli
Wolfgang Pauli
Wolfgang Ernst Pauli was an Austrian theoretical physicist and one of the pioneers of quantum physics. In 1945, after being nominated by Albert Einstein, he received the Nobel Prize in Physics for his "decisive contribution through his discovery of a new law of Nature, the exclusion principle or...
in Zürich, Niels Bohr
Niels Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. Bohr mentored and collaborated with many of the top physicists of the century at his institute in...
in Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...
and Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...
in Rome before he went back to Leipzig assuming a position as privatdozent (lecturer). In 1933, immediately after Hitler came to power, he left Germany, emigrating to work at Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
in 1934. In the fall of 1938, Bloch began working with the University of California at Berkeley 37" cyclotron to determine the magnetic moment of the neutron. Bloch went on to become the first professor for theoretical physics at Stanford. In 1939, he became a naturalized citizen of the United States. During WW II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
he worked on nuclear power
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...
at Los Alamos National Laboratory
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
, before resigning to join the radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
project at Harvard University
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...
.
After the war he concentrated on investigations into nuclear induction and nuclear magnetic resonance
Nuclear magnetic resonance
Nuclear magnetic resonance is a physical phenomenon in which magnetic nuclei in a magnetic field absorb and re-emit electromagnetic radiation...
, which are the underlying principles of MRI
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
. In 1946 he proposed the Bloch equations
Bloch equations
In physics and chemistry, specifically in NMR or MRI , or ESR the Bloch equations are a set of macroscopic equations that are used to calculate the nuclear magnetization M = as a function of time when relaxation times T1 and T2 are present...
which determine the time evolution of nuclear magnetization. He and Edward Mills Purcell
Edward Mills Purcell
Edward Mills Purcell was an American physicist who shared the 1952 Nobel Prize for Physics for his independent discovery of nuclear magnetic resonance in liquids and in solids. Nuclear magnetic resonance has become widely used to study the molecular structure of pure materials and the...
were awarded the 1952 Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...
for "their development of new ways and methods for nuclear magnetic precision measurements." In 1954–1955, he served for one year as the first Director-General of CERN
CERN
The European Organization for Nuclear Research , known as CERN , is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border...
. In 1961, he was made Max Stein Professor of Physics at Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
.
External links
- Biography and Bibliographic Resources, from the Office of Scientific and Technical InformationOffice of Scientific and Technical InformationThe Office of Scientific and Technical Information is a component of the Office of Science within the U.S. Department of Energy...
, United States Department of EnergyUnited States Department of EnergyThe United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material... - http://nobelprize.org/physics/laureates/1952/bloch-bio.html
- http://www-sul.stanford.edu/depts/spc/xml/sc0303.xml
- Oral History interview transcript with Felix Bloch 14 May 1964, American Institute of Physics, Niels Bohr Library and Archives
- Oral History interview transcript with Felix Bloch 15 August 1968, American Institute of Physics, Niels Bohr Library and Archives
- Oral History interview transcript with Felix Bloch 15 December 1981, American Institute of Physics, Niels Bohr Library and Archives
Research resources
- Bloch, F.; Staub, H. "Fission Spectrum", Los Alamos National Laboratory (LANL) (through predecessor agency Los Alamos Scientific Lab), United States Department of Energy (through predecessor agency the US Atomic Energy Commission), (August 18, 1943).
- Felix Bloch Papers, 1931-1987 (33 linear ft.) are housed in the Department of Special Collections and University Archives at Stanford University Libraries