
Atomic clock confirms that Tokyo’s tallest tower is also its most futuristic.
As the tallest structure in Japan, the Tokyo Skytree provides unparalleled views of the city and its surroundings and the exhilaration of standing farther off the ground than anyone in the country who’s not in an airplane. But it turns out there’s something else you can add to what the Skytree offers: time acceleration.
In simplified terms, Einstein’s general theory of relativity holds that time moves more slowly where gravity is heavier, and faster where there’s less gravity. Under that logic, University of Tokyo quantum electronics professor Hidetoshi Katori wanted to see what’s happening with the flow of time at the Skytree’s 450-meter (1,476-foot)-high observation floor. Using an optical lattice clock (a kind of atomic clock accurate up to a one-second differential over 30 billion years), Katori and his research team took measurements and determined that time is indeed moving faster up in the observatory than it is at Tokyo street level.
For each second that passes on the surface, the researchers found that an extra five trillionths of a second have elapsed on the Skytree’s observation floor. Stretched out over the course of an entire day, that works out to an extra four billionths of a second.
Unfortunately, that time acceleration isn’t significant enough for us to take a quick ride in the Skytree’s elevator in order to get a head start on the weekend. However, Katori says he believes there can be practical applications of this knowledge, and considering that the very tip of the Skytree is 634 meters above the ground, it stands to reason that time is passing even more quickly there.
Sources: Kyodo via Hachima Kiko, Mainichi Shimbun, Nature Photonics
Top image: Pakutaso
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