Kenneth Nordtvedt

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Kenneth Leon Nordtvedt (* 16th April 1939 in Chicago , Illinois ) is an American physicist who deals with gravitational physics deals and special experimental tests of relativistic theories of gravitation.

Life

Kenneth Nordtvedt studied at the Massachusetts Institute of Technology (MIT, Bachelor 1960) and at Stanford University , where he graduated in 1962 his master's degree in physics and in 1965 a doctorate was. From 1963 to 1965 he was in the Instrumentation Lab at MIT. From 1965 he was an assistant professor and later a professor at Montana State University in Bozeman . He has now retired.

Nordtvedt is known for suggestions in the 1960s for experiments to test the principle of equivalence . He suggested precise measurements of the distance to the moon with lasers in order to test the strong equivalence principle, whether the gravitational binding energy of the moon contributes in the same way to the inert as to the heavy mass of the moon ( Nordtvedt effect ). According to the strong equivalence principle, this should be the case and gravitational binding energy should behave like all other forms of energy. If one looks at the earth and moon in the gravitational field of the sun , a deviation in the distance measurements should be noticeable if the principle is violated. The general theory of relativity (GTR) does not predict any differences, in contrast to the Brans-Dicke theory , which predicts monthly oscillations in the Earth-Moon distance (depending on the relative position of the moon) with an amplitude of up to 10 m. Measurements in the Lunar Laser Ranging Experiment showed no deviations from the predictions of the ART. The experiments were also a confirmation of the equivalence principle with regard to the different element compositions of the celestial bodies with a relative accuracy of 10 −11 .

In the 1990s, Nordtvedt was on the supervisory body of the NASA / ESA project for a planned test of the equivalence principle in space (STEP, Space Test of Equivalence Principle ). From 1971 to 1973 he was a research fellow of the Alfred P. Sloan Foundation ( Sloan Research Fellowship ). He is a fellow of the American Physical Society . From 1987 he served on the National Science Board during the presidency of Ronald Reagan , as one of the only two university scholars on that board.

From the early 1980s he was also a Republican member of the House of Representatives from Montana for six years and during this time interrupted his research, which had previously been funded by NASA, for example, in the 1970s.

He also dealt with genetic methods in genealogy.

Individual evidence

  1. ↑ Birth dates and career dates according to American Men and Women of Science , Thomson Gale 2005
  2. ↑ Nordtvedt Equivalence Principle for massive bodies , part 1, 2, Physical Review, Volume 169, 1968, pp. 1014/1017.
  3. ^ Nordtvedt in Bertotti (editor) Experimental Gravitation , 56th Enrico Fermi Summer School, Academic Press 1974, Nordtvedt Gravitation Theory. Experimental status from solar system experiments , Science, Volume 178, 1972, pp. 11571-164
  4. ↑ Adelberger, Heckel, Smith, Su, Swanson Eötvös Experiments, Lunar Ranging and the Strong Equivalence Principle , Nature, Volume 34 7, 1990, p. 261 .
  5. ^ NASA Space Grant
  6. ^ The Montana Legislature
personal data
SURNAME Nordtvedt, Kenneth
ALTERNATIVE NAMES Nordtvedt, Kenneth Leon (full name)
BRIEF DESCRIPTION American physicist
DATE OF BIRTH April 16, 1939
PLACE OF BIRTH Chicago , Illinois