Sheldon Lee Glashow | |
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Born | December 5, 1932 New York City, New York, USA |
Nationality | United States |
Fields | Physics |
Institutions | Boston University Harvard University |
Alma mater | Cornell University Harvard University |
Known for | Electroweak theory Criticism of Superstring theory |
Notable awards | Nobel Prize in Physics (1979) |
Sheldon Lee Glashow (born December 5, 1932) is a Nobel Prize winning American physicist. He is the Metcalf Professor of Mathematics and Physics at Boston University.
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Sheldon Lee Glashow was born in New York City to Jewish immigrants from Russia.[1] He attended the Bronx High School of Science in New York City. He was a friend of Steven Weinberg.[2] He 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. He was a visiting professor at MIT in 1974.[2]
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.
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 Harvard physics department and when it embraced string theory, he left.[3] About ten minutes into the TV episode "Strings the Thing" (the second part of The Elegant Universe), he describes it as a discipline distinct from physics and interjects, "...you may call it tumor, if you will...".[4]
He is also a member of the Board of Sponsors of The Bulletin of the Atomic Scientists.[5]
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