21–26 Jun 2026
U. Ottawa - Learning Crossroads (CRX) Building
America/Toronto timezone
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It’s Been a Hot Second: Atomic clocks, timescales, and the redefinition of the SI second

24 Jun 2026, 14:45
30m
U. Ottawa - Learning Crossroads (CRX) Building

U. Ottawa - Learning Crossroads (CRX) Building

100 Louis-Pasteur Private, Ottawa, ON K1N 9N3
Invited Speaker / Conférencier(ère) invité(e) Atomic, Molecular and Optical Physics, Canada / Physique atomique, moléculaire et photonique, Canada (DAMOPC-DPAMPC) (DAMOPC) W2-9 Precision single particle and many-body physics in AMO systems | Physique de précision des particules individuelles et des systèmes à plusieurs corps dans les systèmes AMO

Speaker

Scott Beattie

Description

How do we know what time it is—and how can we ensure that a second measured today will be the same tomorrow, or on the other side of the world? Modern timekeeping answers these questions by tying time to the fundamental properties of atoms, achieving a level of precision that underpins both advanced technologies and fundamental physics.
In this talk, I will describe how atomic clocks are used to realize official time in Canada and the role of the National Research Council’s Frequency and Time Group in generating and maintaining the national timescale. I will outline how national timescales are linked through international comparisons to form International Atomic Time (TAI), and how successive generations of atomic clocks have steadily improved accuracy and stability.
Finally, I will review current international efforts toward a redefinition of the SI second. With optical atomic clocks now surpassing caesium-based standards by more than two orders of magnitude, this redefinition represents a significant step in the evolution of time measurement, with important implications for metrology and emerging technologies.

Keyword-1 atomic clocks
Keyword-2 timescales
Keyword-3 redefinition of the second

Author

Scott Beattie

Presentation materials

There are no materials yet.