John Joseph Hopfield
Encyclopedia
John Joseph Hopfield is an American
scientist most widely known for his invention of an associative neural network
in 1982. It is now more commonly known as the Hopfield Network
.
John Hopfield received his BA from Swarthmore College
, and a Ph.D in physics from Cornell University
in 1958. He spent two years in the theory group at Bell Laboratories, and subsequently was a faculty member at University of California, Berkeley
(physics), Princeton University
(physics), California Institute of Technology
(Chemistry and Biology) and now again at Princeton, where he is the Howard A. Prior Professor of Molecular Biology. For 35 years, he also continued a strong connection with Bell Laboratories.
In 1986 he was a co-founder of the Computation and Neural Systems PhD program at Caltech.
He was awarded the Dirac Medal of the ICTP in 2002 for his interdisciplinary contributions to understanding biology as a physical process, including the proofreading process in biomolecular synthesis and a description of collective dynamics and computing with attractors in neural networks, and the Oliver Buckley Prize of the American Physical Society for work on the interactions between light and solids. He is a member of the National Academy of Sciences, the American Philosophical Society, and the American Academy of Arts and Sciences. He was the President of the American Physical Society in 2006.
His most influential papers have been "The Contribution of Excitons to the Complex Dielectric Constant of Crystals" (1958), describing the polariton
; “Electron transfer between biological molecules by thermally activated tunneling” (1974), describing the quantum mechanics of long-range electron transfers; "Kinetic Proofreading
: a New Mechanism for Reducing Errors in Biosynthetic Processes Requiring High Specificity" (1974); "Neural networks and physical systems with emergent collective computational abilities" (1982) (known as the Hopfield Network) and, with D. W. Tank, “Neural computation of decisions in optimization problems” (1985). His current research and recent papers are chiefly focused on the ways in which action potential
timing and synchrony can be used in neurobiological computation.
He is currently a professor
in the department of Molecular Biology at Princeton University
and is a former President of the American Physical Society
(APS). He previously taught at Princeton in the physics
department and at the California Institute of Technology
. His undergraduate degree, in physics, is from Swarthmore College
(A.B.
, 1954) and his doctorate, also in physics, is from Cornell University
(Ph.D.
, 1958) under the direction of Albert Overhauser
.
Hopfield was born in 1933 to Polish physicist John Joseph Hopfield and his physicist wife Helen Hopfield. Helen was the older Hopfield's second wife. He is the sixth of Hopfield's children and has three children and six grandchildren of his own.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
scientist most widely known for his invention of an associative neural network
Neural network
The term neural network was traditionally used to refer to a network or circuit of biological neurons. The modern usage of the term often refers to artificial neural networks, which are composed of artificial neurons or nodes...
in 1982. It is now more commonly known as the Hopfield Network
Hopfield net
A Hopfield network is a form of recurrent artificial neural network invented by John Hopfield. Hopfield nets serve as content-addressable memory systems with binary threshold units. They are guaranteed to converge to a local minimum, but convergence to one of the stored patterns is not guaranteed...
.
John Hopfield received his BA from Swarthmore College
Swarthmore College
Swarthmore College is a private, independent, liberal arts college in the United States with an enrollment of about 1,500 students. The college is located in the borough of Swarthmore, Pennsylvania, 11 miles southwest of Philadelphia....
, and a Ph.D in physics from Cornell University
Cornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
in 1958. He spent two years in the theory group at Bell Laboratories, and subsequently was a faculty member at University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
(physics), Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....
(physics), California Institute of Technology
California Institute of Technology
The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...
(Chemistry and Biology) and now again at Princeton, where he is the Howard A. Prior Professor of Molecular Biology. For 35 years, he also continued a strong connection with Bell Laboratories.
In 1986 he was a co-founder of the Computation and Neural Systems PhD program at Caltech.
He was awarded the Dirac Medal of the ICTP in 2002 for his interdisciplinary contributions to understanding biology as a physical process, including the proofreading process in biomolecular synthesis and a description of collective dynamics and computing with attractors in neural networks, and the Oliver Buckley Prize of the American Physical Society for work on the interactions between light and solids. He is a member of the National Academy of Sciences, the American Philosophical Society, and the American Academy of Arts and Sciences. He was the President of the American Physical Society in 2006.
His most influential papers have been "The Contribution of Excitons to the Complex Dielectric Constant of Crystals" (1958), describing the polariton
Polariton
In physics, polaritons are quasiparticles resulting from strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation. They are an expression of the common quantum phenomenon known as level repulsion, also known as the anti-crossing principle...
; “Electron transfer between biological molecules by thermally activated tunneling” (1974), describing the quantum mechanics of long-range electron transfers; "Kinetic Proofreading
Kinetic proofreading
Kinetic proofreading is a mechanism for error correction in biological processes, proposed independently by John Hopfield and Jacques Ninio...
: a New Mechanism for Reducing Errors in Biosynthetic Processes Requiring High Specificity" (1974); "Neural networks and physical systems with emergent collective computational abilities" (1982) (known as the Hopfield Network) and, with D. W. Tank, “Neural computation of decisions in optimization problems” (1985). His current research and recent papers are chiefly focused on the ways in which action potential
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
timing and synchrony can be used in neurobiological computation.
He is currently a professor
Professor
A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...
in the department of Molecular Biology at Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....
and is a former President of the American Physical Society
American Physical Society
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...
(APS). He previously taught at Princeton in the 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...
department and at the California Institute of Technology
California Institute of Technology
The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...
. His undergraduate degree, in physics, is from Swarthmore College
Swarthmore College
Swarthmore College is a private, independent, liberal arts college in the United States with an enrollment of about 1,500 students. The college is located in the borough of Swarthmore, Pennsylvania, 11 miles southwest of Philadelphia....
(A.B.
Bachelor of Arts
A Bachelor of Arts , from the Latin artium baccalaureus, is a bachelor's degree awarded for an undergraduate course or program in either the liberal arts, the sciences, or both...
, 1954) and his doctorate, also in physics, is from Cornell University
Cornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
(Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...
, 1958) under the direction of Albert Overhauser
Albert Overhauser
Albert W. Overhauser is an American physicist and member of the National Academy of Sciences. He is best known for his theory of dynamic nuclear polarization, also known as the Overhauser Effect....
.
Hopfield was born in 1933 to Polish physicist John Joseph Hopfield and his physicist wife Helen Hopfield. Helen was the older Hopfield's second wife. He is the sixth of Hopfield's children and has three children and six grandchildren of his own.
External links
- Homepage at Princeton
- http://www.scholarpedia.org/article/User:Hopfield