Speed of Light from Direct Frequency and Wavelength Measurements of the Methane-Stabilized Laser

  title={Speed of Light from Direct Frequency and Wavelength Measurements of the Methane-Stabilized Laser},
  author={Kenneth M. Evenson and Joseph S. Wells and F. Russell Petersen and B. L. Danielson and Gordon W. Day and Richard Lee Barger and John L. Hall},
  journal={Physical Review Letters},
The National Bureau of Standards has had a long history of interest in the speed of light, and no doubt this interest contributed to the measurement described here [1]. As early as 1907, Rosa and Dorsey [2] determined the speed of light from the ratio of the capacitance of a condenser as measured in electrostatic and electromagnetic units. Over the ensuing years NBS developed still other methods to improve upon the accuracy of this important physical constant. By the late 1960s, lasers… Expand

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