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A proposal for three categories of units within the SI

Published

Author(s)

John Lehman, Alan Migdall, Julia Scherschligt

Abstract

In this letter we examine the organization of the traditional base units and defining constants established in the 2019 redefinition of the international system of units (SI). For the next redefinition of the SI, which will accompany the anticipated redefinition of the second, we propose an organizational change to improve clarity while maintaining practicality. We propose three distinct categories of units: The first category comprises the four base-measurement units: The second, meter, kilogram, and ampere. The second contains physiologically-relevant derived units. The third category contains the remaining units derived from the base units.
Citation
Metrologia
Volume
61

Keywords

International System of Units, SI, mol, kelvin, ampere, meter, second, kilogram, candela

Citation

Lehman, J. , Migdall, A. and Scherschligt, J. (2024), A proposal for three categories of units within the SI, Metrologia, [online], https://doi.org/10.1088/1681-7575/ad40af, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=957187 (Accessed April 24, 2025)

Issues

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Created April 29, 2024, Updated April 22, 2025