Where Do We Live? Reflections on Physical Units and the Universal Constants
Physicists are always busy measuring things. Measurement implies methods of measurement and the adoption of arbitrary units in terms of which things are measured. Our arbitrary units have been chosen from a definitely practical standpoint and thus have no direct relation to the fundamental quantities of nature; that is, to the so-called universal constants, the quantities which are not properties of special substances but are fundamental characteristics of the physical world. Let us therefore have a look at the unit systems of physics.
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