The Clock That Redefines the Second
Optical atomic clocks have reached a level of precision that far exceeds the current cesium standard. As the international metrology community converges on a roadmap for 2026, we explore the transition from the 1967 definition of the second to a new optical era, and what this means for the infrastructure of GPS, finance, and global physics.
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Optical clocks use visible light frequencies to achieve precision levels of ten to the negative eighteen.
The current cesium standard loses one second over the entire age of the universe.
International authorities face a twenty twenty-six deadline to choose between specific atoms like ytterbium or strontium.
Current satellite links lack the bandwidth to distribute high-precision optical time signals globally.
A formal redefinition of the second is scheduled for twenty thirty to ensure global financial stability.
New regulations in India will tighten authorized timing sources starting in twenty twenty-six.
- 01Intro1 min
- 02The Limits of Cesium2 min
- 03The Twenty Twenty-Six Crossroads2 min
- 04The Infrastructure of Time2 min
- 05The Long Migration2 min
- 06Outro1 min
- FAQ-redefinition-second - BIPM
- International Committee for Weights and Measures
- Roadmap towards the redefinition of the second
- On the actions to progress on the roadmap for ...
- Présentation PowerPoint - webtai.bipm.org
- arXiv:2503.13278v1 [physics.atom-ph] 17 Mar 2025
- 2020-10-07-optical-clocks
- recommended values of standard frequencies for
- China Optical Clocks Achieves First-Ever Steering of International ...
- Draft Resolutions - CGPM 2026
- Legal Metrology (Indian Standard Time) Rules, 2026 Notified: Major Step Towards “One Nation, One Time”
- Legal Metrology (Indian Standard Time) Rules, 2026 Notified - PIB
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