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George Zweig

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George Zweig (Moskou, 30 mei 1937) is een Amerikaanse fysicus. He was trained as a particle physicist under Richard Feynman.[1] Hij introduceerde, onafhankelijk van Murray Gell-Mann, het quark-model. Later is hij zich gaan bezighouden met neurobiologie. Hij heeft als wetenschappelijk onderzoeker gewerkt bij het Los Alamos National Laboratory en het MIT, en in de financiële dienstverlening.

Biografie

Zweig is geboren in Moskou, Rusland uit een joodse familie.[2] His father was a type of civil engineer known as a structural engineer. He graduated from the University of Michigan in 1959, with a bachelor's degree in mathematics, having taken numerous physics courses as electives. He earned a PhD degree in theoretical physics at the California Institute of Technology in 1964 .

Werk

Zweig voorspelde het bestaan van quarks at CERN, onafhankelijk van Murray Gell-Mann, right after defending his PhD dissertation. Zweig noemde deze "aces", naar de vier bekende kaarten, omdat hij verwachtte dat er vier van deze deeltjes bestonden (op grond van de toen vier bekende leptons).[3][4] The introduction of quarks provided a cornerstone for particle physics.

Like Gell-Mann, he realized that several important properties of particles such as baryons (e.g., protons and neutrons) could be explained by treating them as triplets of other constituent particles (which he called aces and Gell-Mann called quarks), with fractional baryon number and electric charge. Unlike Gell-Mann, Zweig was partly led to his picture of the quark model[5][6] by the peculiarly attenuated decays of the Sjabloon:Mvar meson to 'ρ π', a feature codified by what is now known as the OZI Rule, the "Z" in which stands for "Zweig". In subsequent technical terminology, ultimately Gell-Mann's quarks were closer to "current quarks", while Zweig's to "constituent quarks".[7]

As pointed out by astrophysicist John Gribbin, Gell-Mann deservedly received the Nobel Prize for physics in 1969, for his overall contributions and discoveries concerning the classification of elementary particles and their interactions; at that time, quark theory had not become fully accepted,[8] and was not specifically mentioned in the official citation of the prize. In later years, when quark theory became established as the standard model of particle physics, the Nobel committee presumably felt they couldn't recognize Zweig as the scientist who first spelled out the theory's implications in detail and suggested that they might be real, without including Gell-Mann again. Nevertheless, in 1977 Richard Feynman nominated both Gell-Mann and Zweig for the Nobel prize, presumed to be his only nomination for such.[9] Whatever the reason, despite Zweig's contributions to a theory central to modern physics, he has not yet been awarded a Nobel prize.[10]

Zweig later turned to hearing research and neurobiology, and studied the transduction of sound into nerve impulses in the cochlea of the human ear,[11] and how the brain maps sound onto the spatial dimensions of the cerebral cortex. In 1975, while studying the ear,[12] he discovered a version of the continuous wavelet transform, the cochlear transform.

In 2003, Zweig joined the quantitative hedge fund Renaissance Technologies, founded by the former Cold War code breaker James Simons. He left the firm in 2010.

Once his four year confidentiality agreement with Renaissance Technologies expired, the 78-year-old Zweig returned to Wall Street and co-founded a quantitative hedge fund, called Signition, with two younger partners. They hope to begin trading in 2015. Zweig was quoted as saying "life can be very boring" without work.[13]

Onderscheidingen

Bronnen, noten en/of referenties

Bronnen, noten en/of referenties

  1. º George Zweig. Mathematics Genealogy Project (North Dakota State University) Geraadpleegd op 2010-03-18
  2. º Panos Charitos interviews George Zweig (2013) CERN Interview.
  3. º An SU(3) model for strong interaction symmetry and its breaking
  4. º An SU(3) model for strong interaction symmetry and its breaking II
  5. º Origins of the Quark Model
  6. º Concrete Quarks: The Beginning of the End
  7. º Concrete quarks: CERN 2013 colloquium , ditto, FNAL 2014
  8. º Missing hadronic resonance states predicted by the quark model were only established in the early 1970s. Appreciation that flavor SU(3) reflects nothing beyond the symmetries of the three lightest quarks had to wait until the late 1970s. Understanding of the reason free quark searches were turning up negative was lacking until 1974.
  9. º [ Memories of Murray and the Quark Model]
  10. º [ Schrödinger's Kittens and the Search For Reality]
  11. º (1995). The origin of periodicity in the spectrum of evoked otoacoustic emissions. The Journal of the Acoustical Society of America 98 (4): 2018. DOI:10.1121/1.413320.
  12. º (1976). Basilar Membrane Motion. Cold Spring Harbor Symposia on Quantitative Biology 40: 619–33. DOI:10.1101/SQB.1976.040.01.058., (1976). The cochlear compromise. The Journal of the Acoustical Society of America 59 (4): 975–82. DOI:10.1121/1.380956.
  13. º http://www.wsj.com/articles/at-78-scientist-is-starting-a-hedge-fund-1437693849
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