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Physics research at NIST includes everything from improving the safety of medical radiation procedures to developing future "quantum information" technologies that generate unbreakable codes. NIST provides the measurements, standards, and technical expertise scientists and industries need to push the limits of the fundamental properties of nature.
Atomic clocks: NIST built the world’s first atomic clock, showing how to achieve the precise synchronization now critical to many modern technology systems, from GPS satellites for navigation to stock exchanges. NIST continues to operate atomic clocks, including the U.S. civilian time standard.
Frequency combs: NIST scientists developed the frequency comb, a “ruler of light” that made possible the latest atomic clocks, which may serve as future time standards. Frequency comb applications are also helping to find Earth-like planets, identify atmospheric chemicals and locate gas leaks.
Laser cooling: NIST physicists led the development and application of methods of cooling and trapping atoms with laser light, leading to the creation of new states of matter, advances in experimental quantum computing, and the awarding of three related Nobel Prizes to NIST physicists.
Einstein is reported to have once said that time is what a clock measures. Some say that what we experience as time is really our experience of the phenomenon of entropy, the second law of thermodynamics. Entropy, loosely explained, is the tendency for things to become disorganized. Hot coffee always goes cold. It never reheats itself. Eggs don’t unscramble themselves. Your room gets messy and you