19 December 2015

19 December: Atomic clocks and ultra-precise measurement

Atomic clocks

Today’s researcher works with clocks so accurate, that they only lose a single second every 3 billion years. His research is vital for future technological developments in fields such as communication and navigation in space. Meet Jan W. Thomsen, associate professor of atomic physics and quantum optics at the Niels Bohr Institute.

Has a slowed timepiece ever caused you to be you late? Had it been an atomic clock, the timepiece would never have been to blame. In fact, an atomic clock is so accurate that you would never get to experience that far off moment when it eventually does fall just slightly behind.

Jan W. Thomsen has been interested in questions about time and measurement since his primary and lower secondary school days. This deep-rooted interest drives his research into fundamental quantum mechanics and quantum optics. A revolution in precision time measurement has occurred within the last five to ten years, a field within which Jan W. Thomsen and his team conduct their research.

Ultra precision

Along with his colleagues, Thomsen tries to develop components for atomic clocks. Precise down to billionths of a second, atomic clocks lose or gain less than one second every 3 billion years. Hence, they are the most accurate form of measurement found in the natural sciences. This ultra-precision allows one the opportunity to pose fundamental questions and consider a great many possible applications.

Developing these atomic clocks is vital for future technological developments in fields such as communication and navigation in space, as well as the possible observation of gravitational waves as predicted in Einstein’s Theory of Special Relativity, published in 1905.

Condensing measurements

One attempts to reduce all measurements to the most precise element – time. While not all measurements can be reduced to time, length can.

The accuracy of an atomic clock allows us to observe differences in time between a pair of timepieces, when one is situated just 10 cm above the other. Their performance is not parallel. Based on Einstein’s theory of relativity and on the two different points in time, one can find out how the earth tugs at us and about what can be found in the ground beneath us.

"The applications made possible by these precise measurements are fascinating," states Thomsen.

Reason and mathematics as the driving force

Jan W. Thomsen’s fascination of the subject dates back to his days as a primary and lower secondary school student. The ability to measure so precisely that something about nature can be revealed, this ability to predict and measure, awoke great curiosity in him and has brought Thomsen to where he is today.

"With a large suitcase stuffed with common sense, mathematics and natural laws, one can conduct some fascinating things with natural science and take part in creating things that can help others in a variety of ways. It is incredibly exciting."

Unopened doors

Oftentimes, addressing these topics entails attempting to manoeuvre in the unknown, in areas where no one else has been before – to open new doors and peek into entirely new chambers. By opening these doors, one can use loads of exciting tools. Jan W. Thomsen explains:

"I think that we have it a bit like when Tutankhamun’s tomb was first opened. It had been a long time since anyone had looked into it, and with our research, we are looking into chambers that may have never otherwise been opened. The results we obtain can be used for loads of other fun stuff."

Jan W. Thomsen has earned degrees in Denmark and France, and completed his PhD work in Paris. After having worked abroad for several years, both in France and Holland, Thomsen returned to Denmark to build up his laboratory at the University of Copenhagen’s Niels Bohr Institute.