Friedman, Jerome Isaac (frēdˈmən) [key], 1930–, American physicist, b. Chicago, Ph.D. Univ. of Chicago, 1956. A professor at the Massachusetts Institute of Technology, Friedman won the 1990 Nobel Prize in Physics with Richard E. Taylor and Henry W. Kendall for a series of experiments (1967–73) that showed that protons and neutrons are not fundamental particles of matter but are composed of smaller particles known as quarks. This evidence allowed scientists to develop the Standard Model theory of matter, which states that all matter is made up of combinations of six quarks and six leptons that interact with five types of force particles (see elementary particles).
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