Beyond My Ken (talk | contribs) No edit summary |
83.199.113.29 (talk) This is just facts, and easy to verify |
||
Line 46: | Line 46: | ||
*''Third Workshop on Grand Unification, University of North Carolina, Chapel Hill, April 15–17, 1982'' edited with Paul H. Frampton and Hendrik van Dam (1982) ISBN 3-7643-3105-4 |
*''Third Workshop on Grand Unification, University of North Carolina, Chapel Hill, April 15–17, 1982'' edited with Paul H. Frampton and Hendrik van Dam (1982) ISBN 3-7643-3105-4 |
||
*"Desperately Seeking Superstrings?" with [[Paul Ginsparg]] in ''Riffing on Strings: Creative Writing Inspired by String Theory'' (2008) ISBN 9780980211405 |
*"Desperately Seeking Superstrings?" with [[Paul Ginsparg]] in ''Riffing on Strings: Creative Writing Inspired by String Theory'' (2008) ISBN 9780980211405 |
||
==Controversies== |
|||
In 1998, Sheldon Glashow and [[Sidney Coleman]] published a paper <ref name=Coleman, Glashow 1998>Sidney Coleman and Sheldon Glashow, <i>High-Energy Tests of Lorentz Invariance</i>, [http://arxiv.org/abs/hep-ph/9812418 arXiv:hep-ph/9812418]</ref> suggesting that Lorentz symmetry violation (LSV) could be at the origin of a suppression of the Greisen-Zatsepin-Kuzmin (GZK) cutoff. But the work by [[Luis Gonzalez-Mestres]], that Coleman and Glashow do not cite, is clearly prior to their suggestion. |
|||
In his book ''[[The Trouble With Physics]]'', Lee Smolin, a former doctoral student of Sidney Coleman at Harvard, wrongly attributes to Coleman and Glashow this original idea. Already in a 1996 paper <ref name="Gonzalez-Mestres1996">Luis González-Mestres (June 1996), ''Superluminal Matter and High-Energy Cosmic Rays'', http://arxiv.org/abs/astro-ph/9606054</ref>, Gonzalez-Mestres had also conjectured that superbradyon decay could provide a source of ultra-high energy cosmic rays. |
|||
In April 1997, postulating the existence of a vacuum rest frame and a quadratic momentum dependence for the effective LSV parameters, González-Mestres pointed out <ref name="Gonzalez-Mestres1997a">Luis González-Mestres (April 1997), ''Vacuum Structure, Lorentz Symmetry and Superluminal Particles'', http://arxiv.org/abs/physics/9704017</ref> that Lorentz symmetry violation for "ordinary" particles can lead to a suppression of the GZK cutoff and that, under the same hypothesis, unstable particles can become stable at ultra-high energy. More generally, the stability and decays of ultra-high energy particles would depend on LSV parameters. These original ideas were also presented at the 1997 International Cosmic Ray Conference. <ref name="Gonzalez-Mestres1997b">Luis González-Mestres (May 1997), ''Absence of Greisen-Zatsepin-Kuzmin Cutoff and Stability of Unstable Particles at Very High Energy, as a Consequence of Lorentz Symmetry Violation'', Proceedings of the 25th International Cosmic-Ray Conference, Durban, 30 July - 6 August (published before the conference), Volume 6, Potscheftroomse Universiteit, Copyright Space Research Unit 1997, ISBN 1-86822-281-0 , page 113, paper posted in May 1997, http://arxiv.org/abs/physics/9705031 , also available at http://ccdb4fs.kek.jp/cgi-bin/img/allpdf?199706012 (KISS, KEK, Japan)</ref> |
|||
==See also== |
==See also== |
Revision as of 12:27, 10 June 2011
Sheldon Lee Glashow | |
---|---|
Born | |
Nationality | United States |
Alma mater | Cornell University Harvard University |
Known for | Electroweak theory Criticism of Superstring theory |
Awards | Nobel Prize in Physics (1979) |
Scientific career | |
Fields | Theoretical Physics |
Institutions | Boston University Harvard University University of California, Berkeley |
Sheldon Lee Glashow (born December 5, 1932) is a Nobel Prize winning American theoretical physicist. He is the Metcalf Professor of Mathematics and Physics at Boston University.
Birth and education
Sheldon Lee Glashow was born in New York City to Jewish immigrants from Russia.[1] He graduated from Bronx High School of Science in 1950. Glashow was in the same graduating class as Steven Weinberg, whose own research, independent of Glashow's, would result in the two and Abdus Salam sharing the same 1979 Nobel Prize in Physics (see below).[2] Glashow received a Bachelor of Arts degree from Cornell University in 1954 and a Ph.D. degree in physics from Harvard University in 1959 under Nobel-laureate physicist Julian Schwinger. After graduation, Glashow joined the University of California, Berkeley and worked as an Associate Professor from 1962-66.[3] He was a visiting professor at MIT in 1974.[2]
Glashow is a member of the Board of Sponsors of The Bulletin of the Atomic Scientists.[4]
Research
In 1961, Glashow extended electroweak unification models due to Schwinger by including a short range neutral current , the Z0. The resulting symmetry structure that Glashow proposed, SU(2) × U(1), forms the basis of the accepted theory of the electroweak interactions. For this discovery, Glashow along with Steven Weinberg and Abdus Salam, was awarded the 1979 Nobel Prize in Physics.
In collaboration with James Bjorken, Glashow was the first to predict the charm quark, which he originally named the "charmed quark", in 1964. This work showed that the quark pairs would largely cancel out flavor changing neutral currents, as well as removing a technical disaster for any quantum field theory with unequal numbers of quarks and leptons- an anomaly.
In 1973, Glashow and Howard Georgi proposed the first grand unified theory. They discovered how to fit the gauge forces in the standard model into an SU(5) group, and the quarks and leptons into two simple representations. Their theory qualitatively predicted the general pattern of coupling constant running, with plausible assumptions, it gave rough mass ratio values between third generation leptons and quarks, and it was the first indication that the law of Baryon number is inexact, that the proton is unstable. This work was the foundation for all future unifying work.
Superstring theory
Glashow is a notable skeptic of Superstring theory due to its lack of experimentally testable predictions. He had campaigned to keep string theorists out of the Harvard physics department, though the campaign failed.[5] About ten minutes into "Strings the Thing", the second episode of The Elegant Universe TV series, he describes superstring theory as a discipline distinct from physics, saying "...you may call it tumor, if you will...".[6]
Works
- The charm of physics (1991) ISBN 0-88318-708-6
- From alchemy to quarks: the study of physics as a liberal art (1994) ISBN 0-534-16656-3
- Interactions: a journey through the mind of a particle physicist and the matter of this world (1988) ISBN 0-446-51315-6
- First workshop on grand unification: New England Center, University of New Hampshire, April 10–12, 1980 edited with Paul H. Frampton and Asim Yildiz (1980) ISBN 0-915692-31-7
- Third Workshop on Grand Unification, University of North Carolina, Chapel Hill, April 15–17, 1982 edited with Paul H. Frampton and Hendrik van Dam (1982) ISBN 3-7643-3105-4
- "Desperately Seeking Superstrings?" with Paul Ginsparg in Riffing on Strings: Creative Writing Inspired by String Theory (2008) ISBN 9780980211405
Controversies
In 1998, Sheldon Glashow and Sidney Coleman published a paper Cite error: The <ref>
tag has too many names (see the help page). suggesting that Lorentz symmetry violation (LSV) could be at the origin of a suppression of the Greisen-Zatsepin-Kuzmin (GZK) cutoff. But the work by Luis Gonzalez-Mestres, that Coleman and Glashow do not cite, is clearly prior to their suggestion.
In his book The Trouble With Physics, Lee Smolin, a former doctoral student of Sidney Coleman at Harvard, wrongly attributes to Coleman and Glashow this original idea. Already in a 1996 paper [7], Gonzalez-Mestres had also conjectured that superbradyon decay could provide a source of ultra-high energy cosmic rays.
In April 1997, postulating the existence of a vacuum rest frame and a quadratic momentum dependence for the effective LSV parameters, González-Mestres pointed out [8] that Lorentz symmetry violation for "ordinary" particles can lead to a suppression of the GZK cutoff and that, under the same hypothesis, unstable particles can become stable at ultra-high energy. More generally, the stability and decays of ultra-high energy particles would depend on LSV parameters. These original ideas were also presented at the 1997 International Cosmic Ray Conference. [9]
See also
References
- Notes
- ^ Sheldon Lee Glashow - Britannica Encyclopedia
- ^ a b Glashow's autobiography on the Nobel foundation website
- ^ http://www.jewishvirtuallibrary.org/jsource/biography/glashow.html
- ^ Bulletin of the Atomic Scientists
- ^ Jim Holt, "Unstrung", The New Yorker, October 2, 2006
- ^ "[T]here ain't no experiment that could be done nor is there any observation that could be made that would say, `You guys are wrong.' The theory is safe, permanently safe." He also said, "Is this a theory of Physics or Philosophy? I ask you" NOVA interview
- ^ Luis González-Mestres (June 1996), Superluminal Matter and High-Energy Cosmic Rays, http://arxiv.org/abs/astro-ph/9606054
- ^ Luis González-Mestres (April 1997), Vacuum Structure, Lorentz Symmetry and Superluminal Particles, http://arxiv.org/abs/physics/9704017
- ^ Luis González-Mestres (May 1997), Absence of Greisen-Zatsepin-Kuzmin Cutoff and Stability of Unstable Particles at Very High Energy, as a Consequence of Lorentz Symmetry Violation, Proceedings of the 25th International Cosmic-Ray Conference, Durban, 30 July - 6 August (published before the conference), Volume 6, Potscheftroomse Universiteit, Copyright Space Research Unit 1997, ISBN 1-86822-281-0 , page 113, paper posted in May 1997, http://arxiv.org/abs/physics/9705031 , also available at http://ccdb4fs.kek.jp/cgi-bin/img/allpdf?199706012 (KISS, KEK, Japan)
External links
- Nobel lecture
- Biography and Bibliographic Resources, from the Office of Scientific and Technical Information, United States Department of Energy
- Sheldon Lee Glashow
- Interview with Glashow on Superstrings
- Contributions to the theory of the unified weak and electromagnetic interaction between elementary particles, including inter alia the prediction of the weak neutral current.
- Sheldon Glashow Boston University Physics Department
- Sheldon Glashow Photos