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The Future of Quantum Based Measurements and the SI



Carl J. Williams


The U.S. National Institute of Standards and Technology (NIST), along with other NMIs, is preparing for a new era in the history of metrology made possible by the growing use of quantum-based standards and measurements. This development will dramatically alter many of our conventional practices, and will influence how NMIs approach their missions. That is as it should be. Metrology is not about simply maintaining the status quo and our traditional responsibility to realize, maintain, and disseminate units. Metrology must constantly evolve to meet the ever-changing needs of commerce, science, and engineering. It is the infra-technology that drives and supports the world economy, figuring critically in 80% of all global trade. Quantum metrology is desirable in itself because it promises a new level of precision and accuracy. But is also in keeping with the philosophy behind the upcoming redefinition of the SI units, expected in 2018, in which units will be based on fundamental constants that are based on quantum phenomena. What will quantum metrology mean in practical terms? NIST has developed some definitions that help guide and focus our efforts. They may be useful to others.
Proceedings of the International Summer School “Enrico Fermi” Vol. 196
Publisher Info
IOS Press, Amsterdam, -1


International System of Units, Quantum Based Measurements, Quantum Metrology


Williams, C. (2017), The Future of Quantum Based Measurements and the SI, Proceedings of the International Summer School “Enrico Fermi” Vol. 196, IOS Press, Amsterdam, -1 (Accessed May 29, 2024)


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Created December 1, 2017, Updated June 25, 2018