Eddington numbers
Stories from Physics
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In astrophysics, the Eddington number is the number of protons in the observable universe. He defined it as NEdd= 136 x 2 256 which is approximately 1.575 x 10 79.
In addition to his scientific studies, Eddington was a keen cyclist, a hobby which led to his proposal of a different kind of metric. A Google search is more likely to bring up the Eddington number as the number of times a cyclist has cycled a particular distance in miles. For example, an Eddington number of 20 would indicate a cyclist had cycled more than 20 miles on 20 occasions.
References
Eddington numbers
A. Eddington, The Philosophy of Physical Science. Nature vol. 148, pp, 140–141, 1941.
G. Srinivasan, What are the Stars? Berlin, Springer-Verlag, 2014 p. 32
