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Adjusting the Values of the Fundamental Constents



Peter J. Mohr, Barry N. Taylor


In order to compare theoretical predictions to experimental measurements in many basic studies and applications of physics, it is necessary to know the value of one or more of the fundamental physical constants, such as the electron mass, or energy conversion factors, such as the relation between the electron volt and the joule. Many other fields of science and technology require values of the constants as well. For such purposes, one looks up and uses the latest values of the necessary constants in a suitable table. However, the source of the numbers in the table is often not given much thought, nor is it critical in most cases. This paper provides a discussion of the physics and metrology behind the latest CODATA recommended values of the fundamental constants.
Physics Today
No. 3


electron anomalous magnetic moment, electron mass, fundamental constants, gravitational constant, hydrogen energy levels, quantum electrodynamics


Mohr, P. and Taylor, B. (2001), Adjusting the Values of the Fundamental Constents, Physics Today (Accessed May 18, 2024)


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Created March 1, 2001, Updated February 17, 2017