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From Artefacts to Atoms--The BIPM and the Search for Ultimate Measurement Standards

NIST Colloquium image

The International Bureau of Weights and Measures (BIPM) was created by the Metre Convention, an intergovernmental treaty signed in Paris on 20 May 1875 by seventeen States, including the USA. The Convention also established the formal structure within which Member Governments could establish and maintain a uniform and accurate international system of units, now known as the International System of Units (SI).

In this lecture, Dr. Quinn will outline the origins of the Metre Convention, the creation of the BIPM and its development since 1875, and the parallel move from units of measurement based on material artefacts to units based on the constants of nature. He will end with a description of a simple device made from Lego© blocks and a loudspeaker that demonstrates the principles of the watt balance, one of the ways of realizing the future definition of the kilogram based on a fixed numerical value for the Planck constant.

Watch Quinn describe the "Defining the kg exhibit" at the Royal Society Summer Science Exhibition 2013.

Anyone outside NIST wishing to attend must be sponsored by a NIST employee and receive a visitor badge. For more information, contact Stephanie Shaw at 301-975-2667. Colloquia are videotaped and available in the NIST Research Library.

Terry Quinn, Emeritus Director, Bureau International des Poids et Mesures

Created May 24, 2013, Updated January 5, 2017