2021/05/17 by Paul Quincey · 1 citation
Decision Sciences · Physics and Astronomy · #Experimental and Theoretical Physics Studies #Quantum and Classical Electrodynamics #Scientific Measurement and Uncertainty Evaluation #physics.class-ph
paper · pdf · doi:10.1088/1681-7575/ac023f
published as Metrologia 58 053002 (2021) · Accepted for publication by Metrologia
openalex publication_date 2021/05/17 · openalex created_date 2021/05/24 · arxiv created 2021/08/10 · arxiv updated 2021/08/25 · openalex updated_date 2026/07/28
A recent Letter proposed changing the dimensionless status of the radian and steradian within the SI, while allowing the continued use of the convention to set the angle 1 radian equal to the number 1 within equations, providing this is done explicitly. This would bring the advantages of a physics-based, consistent, and logically-robust unit system, with unambiguous units for all physical quantities, for the first time, while any upheaval to familiar equations and routine practice would be minimised. More details of this proposal are given here. The only notable changes for typical end-users would be: improved units for the quantities torque, angular momentum and moment of inertia; a statement of the convention accompanying some familiar equations; and the use of different symbols for h-bar the action and h-bar the angular momentum, a small step forward for quantum physics. Some features of the proposal are already established practice for quantities involving the steradian such as radiant intensity and radiance.