Optical Clocks and Redefining the Second | UPSC Focus
Redefining the Second: Intercontinental Optical Clock Comparison Explained In a remarkable leap for precision timekeeping, scientists across continents have recently compared multiple high-accuracy optical clocks to lay the groundwork for redefining the SI unit of time — the second . This milestone experiment is not only significant for global science and technology but also offers rich material for UPSC, GPSC, and other competitive exams . This article explores what optical clocks are, how the international experiment was conducted, and why it matters in the context of science, measurement systems, and policy relevance. What Are Optical Clocks and How Do They Work? Optical clocks are the most accurate timekeeping devices ever created. Unlike traditional atomic clocks based on cesium atoms (which oscillate at microwave frequencies), optical clocks use atoms like strontium, ytterbium, or aluminum that oscillate at optical (visible light) frequencies — offering up to 100 tim...