Hall, John Lewis
John Lewis Hall, 1934–, American physicist, b. Denver, Colo., Ph.D. Carnegie Institute of Technology, 1961. He has been a researcher at the National Bureau of Standards in Boulder, Colo., since 1962. Hall, Roy Glauber, and Theodor Hänsch shared the 2005 Nobel Prize in Physics for their work in advancing optics technology. Hall and Hänsch are credited with developing laser-based precision spectroscopy, which enables the color of the light of atoms and molecules to be determined with tremendous precision. The technique, which aids in precise timing in communication systems, provided the foundation for the development of extremely accurate clocks and improved global positioning system technology.