Accreditation and Quality Assurance

, Volume 16, Issue 12, pp 657–658 | Cite as

Unresolved concerns about the “new SI”

  • Jack Miller
  • Theodore P. Hill
  • Albert Censullo
Letter to the Editor

Dear Sirs,

The International Committee for Weights and Measures (CIPM) has proposed new definitions of four of the seven base units of the SI. The definitions of the proposed “new SI” have been published [1] and are available on the BIPM website [2], and have been the subject of lively discussions in the literature and in private communications. A number of concerns about the new SI have been raised in this journal and elsewhere [3, 4, 5, 6, 7, 8, 9, 10, 11]. We feel that these concerns have not been adequately addressed to date. Since the new SI definitions are to be formally proposed in a resolution to be considered in late October at the General Conference on Weights and Measures, this discussion has some urgency.

In this letter, we focus on the new SI definition of the kilogram and specifically that it fails to meet three of the criteria for a good reference quantity as presented by Mills et al. in Ref. [1] that (1) it “should preferably be as simple as possible both to comprehend...


Cesium Base Unit Alternative Definition Exact Mass Acceptable Alternative 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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    Chemistry International (2011) The kilogram in the “New SI”.

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Jack Miller
    • 1
  • Theodore P. Hill
    • 2
  • Albert Censullo
    • 3
  1. 1.Lawrence Berkeley National LaboratoryBerkeleyUSA
  2. 2.School of MathematicsGeorgia Institute of TechnologyAtlantaUSA
  3. 3.California Polytechnic State UniversitySan Luis ObispoUSA

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