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Atomic Clocks

Atomic Clock News

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These stories highlight advances in atomic clock science at NIST.

James Thompson with experiment.

Quantum Spin Squeezing Gets Real

Today's atomic clocks are ridiculously accurate. The best of them tell time so well that if they had been running since the Big Bang, by now they would not have
Clock

Today, Pause for a Second

For the great majority of human history, the earth's rotation—the apparent motion of the sun and stars across the sky—kept time far more precisely than any
sundial in NIST Gaithersburg courtyard. The gnomon, several hour markers and the word "time" are visible.

What, Then, Is Time?

When asked to contribute an essay on some aspect of timekeeping, I had a flashback to the first day of my senior year in high school in Princeton, New Jersey
NIST physicist Judah Levine with the NIST time scale, a digital clock face reading 14:33:34 and a bank of atomic clocks.

Everyday Time and Atomic Time: Part 1

As a physicist in the National Institute of Standards and Technology (NIST) Time and Frequency Division, I have worked in the general area of operating atomic
Created September 6, 2024, Updated October 10, 2024