On 8/10/2011 11:24 PM, Stephen P. King wrote:
And interesting choice of examples since that exactly what man has done. The speed of light is nothing but a conversion constant between units. In 1983 the speed of light in SI units was *defined* to be 299,792,458 m/s.

Umm, not so fast. The permitivity and permiability of the vacuum are not set by prior theory! It is still only a known fact due to measurement.

No. The length of the meter was set as the distance traveled by light in 1/299792458 of a second. So permitivity and permiabilty are not fundamental but are derived values (for the vacuum).


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