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Home > News > Everlasting clock

Everlasting clock

Berkeley Engineer Spring 2013
May 1, 2013
This article appeared in Berkeley Engineer magazine, Spring 2013
  • In this issue

    Features

    Critical making comes to campus

    Experiential ed

    Greening the factory floor

    Dean’s Word

    Upfront

    • Engineering benchmarks for cap-and-trade
    • Welcoming a new chancellor
    • RadMAP rollout
    • Mind the gap
    • EECS offers online master’s program
    • Introducing the Dreambox
    • Q+A: Oxford-bound
    • Comments

    Breakthroughs

    • To a fault
    • A hot spot
    • Mind readers
    • Everlasting clock
    • Streamlined

    Alumni notes

    • Chair man
    • Farewell

    Download this issue

  • Past issues

Tongcang Li and Xiang ZhangTongcang Li and Xiang Zhang have created an experimental design of a four-dimensional space-time crystal that, in principle, can keep perfect time forever. (Photo by Roy Kaltschmidt)An eternal clock that would always keep accurate time, even after the heat-death of the universe, is no longer just an intriguing concept. A team of scientists at Lawrence Berkeley National Laboratory, led by mechanical engineering professor Xiang Zhang, has outlined an experimental design of a four-dimensional “space-time crystal” that can keep perfect time forever—in principle. The design of their structure hinges upon a ring of charged particles; a magnetic flux will change the energy levels of the system and make the structure rotate at its lowest quantum energy state, both continually and permanently. There are also other relevant applications for this groundbreaking design, including the study of physics as well as phenomena in quantum mechanics.

Topics: Research, Faculty, Mechanical engineering
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