Pursuing the

Ultimate One Second

The optical lattice clock enables
us to explore space-time phisics

Pursuing the Ultimate One Second

Human history has been characterized by tireless explorations of time. Almanacs compiled in Egypt by observation of celestial motion made possible the forecasting of when the next flooding of the Nile might come, enabling uninterrupted farming in the fertile land. The land then became the basis of ancient Egyptian prosperity. Following Galileo Galilei, who had discovered the isochronism of the pendulum in the 16th century, Christiaan Huygens built sophisticated pendulum clocks that became important technology in the Age of Discovery. The cesium atomic clock, an invention by Louis Essen, defined one second in 1967 and ....Continued


2016.xx.xx Homepage was renewed
2016/8/16 PRESS:
" Height difference measurement through comparison between optical lattice clocks: New application of clocks as a probe for crustal activities"
2016/4/18 International workshop report:
"View From…Challenges in Precision Science, A never-ending quest " was published in Nature Photonics, April 2016
2016/3/1 PRESS:
"Accelerating comparisons of ytterbium and strontium optical lattice clocks: Swift, ultra-precise measurements of frequency ratios may open new windows for science"
2016/2/1 Prof. Katori was awarded
"JSAP Outstanding Achievement Award" for "Pioneering research on optical lattice clocks"

See the past information

This project has been jointly implemented with the following institutions:

The University of Tokyo
Japan Science and Technology Agency