Sunday, February 19, 2012: 1:00 PM-2:30 PM
Room 208-209 (VCC West Building)The International System of Units (SI) is the common basis for consistent measurement for all of science and technology. Traceability to the metric system is one means to ensure fair trade and equitable commerce. National metrology institutes implicated in the Convention of the Meter are working to revise the definitions of four base units — the kilogram (kg), ampere (A), mole (mol), and kelvin (K) — by using fixed and exact values for some fundamental constants: Planck's constant (h), the Avogadro number (NA), the elementary charge (e), and the Boltzmann constant (kB). This change echoes the 1983 redefinition of the meter, which now relies on a fixed and exact value for the speed of light (c). One visible consequence of the redefinition will be that the International Prototype of the Kilogram, an artifact standard made from Pt-Ir, will no longer define the unit of mass, marking the end of the era where human-made objects, rather than nature itself, sets the reference for our system of units. Attendees will learn about the current SI, the proposed new definitions, and the latest experimental and theoretical knowledge that will be incorporated to set the values for the constants. Because the metric system is widely implemented and virtually everyone is affected by the system of measurement, speakers also will discuss the challenges associated with informing, educating, and engaging the global community to pave the way for a successful introduction in the coming years.
Alan G. Steele, National Research Council of Canada
James K. Olthoff, National Institute of Standards and Technology