The graphs on this page were formulated to show the consistent trends in light speed, Planck's constant, and mass as measured and accepted scientifically in the years indicated.   The light speed measurements are those accepted by Professor Raymond Birge until 1941 and may be referenced, along with many more, in the abundance of charts and footnotes in Atomic Constants, Light and Time. 

References for the Planck particle and mass measurements are at the bottom of this page.

                                                            Light Speed (c)

 

Year         km/sec 1874.8 299990 1879.5 299910 1882.7 299860 1882.8 299853 1902.4 299901 1906 299803 1923 299795 1926.5 299798 1928 299786 1932.5 299774 1936.8 299771 1937 299771 1940 299776

Planck's Constant (h)

 

Years   1939 1941 1947 1950 1952 1955 1963 1965 1969 1973 1986 1998 ergsec  x10-27 6.6214 6.6242 6.6237 6.62363 6.6252 6.62517 6.62559 6.62592 6.626196 6.626227 6.626076 6.626069

Mass  (m)

References by year for both h and m in the above charts:

1939 -- Dunnington, F.G., The Atomic Constants, Reviews of Modern Physics, 11 (2), 65-83, Apr. 1939

1941 -- Birge, R.T., A New Table of Values of the General Physical Constants, Reviews of Modern Physics, 13 (4), 233-239, Oct. 1941

1947 -- DuMond, J.W.M., and E.R. Cohen, Our Knowledge of the Atomic Constants F, N, m and h in 1947, and of Other Constants Derivable Therefrom, Reviews of Modern Physics, 20 (1), 82-108, Jan. 1948

1950 --  Bearden, J.A., and H.M. Watts, A Re-Evaluation of the Fundamental Atomic Constants, Physical Review, 81, 73-81, Jan. 1, 1951

1952 -- DuMond, J.W.M., and E.R. Cohen, Least Squares Adjustment of the Atomic Constants, 1952, Reviews of Modern Physics, 25 (3), 691-708, Jul. 1953

1955 --  Cohen, E.R., et al., Analysis of Variance of the 1952 Data on the Atomic Constants and a New Adjustment, 1955, Reviews of Modern Physics, 27 (4), 363-380, Oct. 1955

1963 --  Cohen, E.R., and J.W.M. DuMond, Present Status of our Knowledge of the Numerical Values of the Fundamental Constants, p.152-186, Proceedings of the Second International Conference on Nuclidic Masses, Vienna, Austria, July 15-19, 1963, W.H. Johnson, Jr., editor, Springer-Verlag, Wien, 1964

1965 -- Cohen, E.R., and J.W.M. DuMond, Our Knowledge of the Fundamental Constants of Physics and Chemistry in 1965, Reviews of Modern Physics, 37 (4), 537-594, Oct. 1965

1969 -- Taylor, B.N., W.H. Parker, D.N. Langenberg, Determination of e/h Using Macroscopic Quantum Phase Coherence in Superconductors: Implications for Quantum Electrodynamics and the Fundamental Physical Constants, Reviews of Modern Physics, 41 (3), 375-496, Jul. 1969

1973 --  Cohen, E.R., and B.N. Taylor, The 1973 Least-Squares Adjustment of the Fundamental Constants, Journal of Physical and Chemical Reference Data, 2 (4), 663-718, 1973

1986 -- E.R. Cohen , B.M. Taylor, The 1986 Adjustment of the Fundamental Physical Constants, Codata Bulletin #63, Pergamum Press, Nov. 1986

1998 -- P.J. Mohr and B.N.Taylor, Codata Recommended Values of the Fundamental Physical Constants, 1998,  Reviews of Modern Physics, April, 2000  http://physics.nist.gov/constants

 

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