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James Bjorken

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Nationality  American
Fields  Theoretical physics
Institutions  Fermilab, SLAC
Doctoral students  Davison Soper
Name  James Bjorken
Awards  Wolf Prize in Physics
Role  Physicist

James Bjorken httpsuploadwikimediaorgwikipediacommonscc

Born  June 22, 1934 (age 81)Chicago, Illinois, United States (1934-06-22)
Alma mater  MIT (B.S., 1956)Stanford University (Ph.D., 1959)
Known for  Bjorken scaling, Co-predicting the charm quark
Notable awards  Putnam Fellow (1954)Heineman Prize (1972)E. O. Lawrence Award (1977)Pomeranchuk Prize (2000)ICTP Dirac Medal (2004)Wolf Prize in Physics (2015)European Physical Society High Energy and Particle Physics Prize (2015)
Books  In Conclusion: A Collection of Summary Talks in High Energy Physics
Education  Stanford University, Massachusetts Institute of Technology

James Bjorken | Wikipedia audio article

James Daniel "BJ" Bjorken (born 1934) is an American theoretical physicist. He was a Putnam Fellow in 1954, received a BS in physics from MIT in 1956, and obtained his PhD from Stanford University in 1959. He was a visiting scholar at the Institute for Advanced Study in the fall of 1962. Bjorken is Emeritus Professor at the Stanford Linear Accelerator Center, and was a member of the Theory Department of the Fermi National Accelerator Laboratory (1979–1989).


James Bjorken SLAC and Stanfords James D Bjorken Shares 2015 Wolf Prize in

He was awarded the Dirac Medal of the ICTP in 2004; and, in 2015, the Wolf Prize in Physics and the EPS High energy and particle physics prize. (de:High Energy and Particle Physics Prize)

James Bjorken SLAC and Stanfords James D Bjorken Receives 2015 High Energy and

James Bjorken y Richard Feynman


James Bjorken SLAC and Stanfords James D Bjorken Shares 2015 Wolf Prize in

Bjorken discovered in 1968 what is known as light-cone scaling, (or Bjorken scaling) a phenomenon in the deep inelastic scattering of light on strongly interacting particles, known as hadrons (such as protons and neutrons): Experimentally observed hadrons behave as collections of virtually independent point-like constituents, when probed at high energies.

James Bjorken Wolf Prize In Physics Awarded To James Bjorken Science 20

Properties of these hadrons scale, that is, they are determined not by the absolute energy of an experiment, but, instead, by dimensionless kinematic quantities, such as a scattering angle or the ratio of the energy to a momentum transfer. Because increasing energy implies potentially improved spatial resolution, scaling implies independence of the absolute resolution scale, and hence effectively point-like substructure.

James Bjorken Wolf Prize In Physics Awarded To James Bjorken Science 20

This observation was critical to the recognition of quarks as actual elementary particles (rather than just convenient theoretical constructs), and led to the theory of strong interactions known as quantum chromodynamics, where it was understood in terms of the asymptotic freedom property. In Bjorken's picture, the quarks become point-like, observable objects at very short distances (high energies), shorter than the size of the hadrons.

Bjorken was also among the first to point out to the phenomena of jet quenching in heavy ion collisions in 1982.

Richard Feynman subsequently reformulated this concept into the parton model, used to understand the quark composition of hadrons at high energies. The predictions of Bjorken scaling were confirmed in the early late 1960s electroproduction experiments at SLAC, in which quarks were seen for the first time. The general idea, with small logarithmic modifications, is explained in quantum chromodynamics by "asymptotic freedom".

Bjorken co-authored, with Sidney Drell, a classic companion volume textbook on relativistic quantum mechanics and quantum fields.


  • J.D. Bjorken, S. Drell (1964). Relativistic Quantum Mechanics. McGraw-Hill. ISBN 0-07-005493-2. 
  • J.D. Bjorken, S. Drell (1965). Relativistic Quantum Fields. McGraw-Hill. ISBN 0-07-005494-0. 
  • Selected papers

  • J. D. Bjorken (1968). "Current Algebra at Small Distances", in Proceedings of the International School of Physics Enrico Fermi Course XLI, J. Steinberger, ed., Academic Press, New York, pp. 55–81. Online, SLAC-PUB-338
  • J.D. Bjorken (1969). "Asymptotic Sum Rules at Infinite Momentum". Physical Review. 179 (5): 1547–1553. Bibcode:1969PhRv..179.1547B. doi:10.1103/PhysRev.179.1547. 
  • J.D. Bjorken (1982). "Energy Loss of Energetic Partons in Quark-Gluon Plasma: Possible Excitation of High pT Jets in Hadron-Hadron Collisions.". FERMILAB-Pub-82/59-THY. 
  • Full list of papers

    INSPIRE-HEP -- Bjorken


    James Bjorken Wikipedia