Fundamental Constants

Time and Motion - A report for the Royal Society by David Bradley

Weighing up units and constants - At the heart of science and technology are measurements and accurate, reliable measurements underpin the experiments and systems on which much human activity is based. From international trade to high-technology manufacturing, from human health and safety to the protection of the environment and global climate studies. Without precision measurements scientists would not be able to carry out the essential tests of scientific theory upon which all these activities depend. It is in this light that the Royal Society meeting "The fundamental constants of physics, precision measurements and SI base units", held in 2005 sought to discuss precision measurements, their origins and limitations and most importantly how all fundamental units of measure from the humble kilogram to the to the unit of temperature, the Kelvin, which is based on the triple point of water, but could be defined on the basis of nature's physical constants.

There are numerous research groups and organisations whose primary interest is in the field of units of measurement and many of these were represented at the meeting and speakers touched on the many disparate strands of this important field from how to choose the best values for units to the increasingly sophisticated demands on measurements from science, technology and all their applications.

Read on... NIST and Fundamental Constants