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The physical basis of natural units and truly fundamental constants

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Abstract

The natural unit system, in which the value of fundamental constants such as c and ℏ are set equal to one and all quantities are expressed in terms of a single unit, is usually introduced as a calculational convenience. However, we demonstrate that this system of natural units has a physical justification as well. We discuss and review the natural units, including definitions for each of the seven base units in the International System of Units (SI) in terms of a single unit. We also review the fundamental constants, which can be classified as units-dependent or units-independent. Units-independent constants, whose values are not determined by human conventions of units, may be interpreted as inherent constants of nature.

Keywords

Natural Unit Fundamental Constant Thermodynamic Temperature Luminous Intensity Planck Unit 
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© Società Italiana di Fisica and Springer 2012

Authors and Affiliations

  1. 1.Department of Postsecondary Teaching and LearningUniversity of MinnesotaMinneapolisUSA
  2. 2.Department of PhysicsUniversity of Massachusetts-DartmouthNorth DartmouthUSA

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