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Colloquia & Seminars

Physics Department Colloquium
Atomic Clocks Does Anybody Really Know What Time It Is?
Time: 4:00 PM
Place: 2241 Chamberlin Hall (coffee at 330 pm)
Speaker: Thomas R. O'Brian, National Institute of Standards and Technology (NIST) and JILA
Abstract: Time is the most accurately measured absolute quantity. The world's best atomic clocks at the National Institute of Standards and Technology (NIST) measure time with absolute uncertainties about 8 x 10-18, the equivalent of one second in 4 billion years. At this precision, relativistic time dilation is evident at jogging speeds or 10 cm changes in altitude. We will discuss how atomic timekeeping underpins a broad range of our technology infrastructure, enables innovative measurements for everything from brain activity to mineral exploration - and how related to atomic timekeeping has stimulated some of the most important advances in atomic and optical physics.
Host: Department of Physics
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