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Keeping Time with a Mercury Atom 153

Roland Piquepaille writes "The National Institute of Standards and Technology (NIST) has announced that a new experimental atomic clock based on a single mercury atom is now at least five times more precise than NIST-F1, the U.S. standard clock. This mercury atomic clock 'would neither gain nor lose a second in about 400 million years' while it would take 'only' 70 million years to NIST-F1, based on a 'fountain' of cesium atoms, to gain or lose a second. But even if this new kind of optical atomic clock is more accurate than cesium microwave clocks, it will take a while before such a design can be accepted as an international standard. A ZDNet summary contains pictures and more details about the world's most precise clock."
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Keeping Time with a Mercury Atom

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  • 400 million years (Score:2, Insightful)

    by gfody ( 514448 ) on Sunday July 16, 2006 @02:26AM (#15727047)
    It's easy to make impressive statements like that when you know nobody will be around to prove you wrong!
  • by Umbral Blot ( 737704 ) on Sunday July 16, 2006 @02:37AM (#15727077) Homepage
    Relativity doesn't make clocks less useful, in fact it makes them more useful (because you can use them to figure out how fast you are going as well). And assuming that the clock remains under constant acceleration there is no reason to believe that relativity would make it less accurate.
  • by evilviper ( 135110 ) on Sunday July 16, 2006 @03:02AM (#15727123) Journal
    It's easy to make impressive statements like that when you know nobody will be around to prove you wrong!

    Complete nonsense. This isn't a "prediction", it's a mathematical number/time. Like any other number/time, you can easily convert it into shorter time-frames.

    1 sec in 400 million years is ==
        1/2 sec in 200 million years
        1/4 sec in 100 million years
        1/8 sec in 50 million years

    That means it is accurate to 0.000000025ths of a second in 10 years... A more partical time-frame, which can be tested fairly easily.
  • Upper Limit? (Score:2, Insightful)

    by NexFlamma ( 919608 ) on Sunday July 16, 2006 @03:20AM (#15727158) Homepage
    At what point do people simply say that our time keeping methods are good enough?

    We already have a clock that only loses 1 second every 70 million years! The odds of the current time keeping system (or mankind, for that matter) continuing in it's current form for the next 70 million years are rather low, so why do we really need one that only loses a second every 400 million?

    Sure, it's nice to be able to improve, but can't the research money go to something more useful? Like, maybe cancer research or studies into how we can build giant robots that transform into dinosaurs...
  • by voice_of_all_reason ( 926702 ) on Sunday July 16, 2006 @03:20AM (#15727159)
    Actually, the logical design of the clock will last 40 billion years until it produces an error. I'm quite sure we will never design any sort of mechanical device can actually last that long to find out.

    //unless you socket it with a zod rune...
  • Accuracy (Score:2, Insightful)

    by thorndt ( 814642 ) on Sunday July 16, 2006 @03:43AM (#15727193)
    I'm suspecting that this level of accuracy would be quite useful in high-end scientific experiements--not so much for general wall-clock settings.
    For example, measuring the duration of extremely short events--like in particle accelerators.
  • That means it is accurate to 0.000000025ths of a second in 10 years... A more partical time-frame, which can be tested fairly easily.

    How, exactly?

    Only test that I can think of would be to build two of these, plus a control of some sort, and leave them right next to each other for ten years. Only the control will be less accurate than the device you're measuring...
  • by Lumpy ( 12016 ) on Sunday July 16, 2006 @08:39AM (#15727664) Homepage
    That an it will help prove my Theory that there is a black hole in time here on the planet earth. AS we age we accelerate towards the black hole and therefore experience time distortion. Think about it. As a child summer took F-O-R-E-V-E-R. As a Teen it took about what felt like the right amount of time. As a Young Adult in college it seems like summer was shorter than normal. A person in their 40's summer feels like about 3 weeks and other effects of time distortion take effect.... Week-ends feel like they last ony a single day. And the inconsistancies also start showing as the time gravitional waves pass by you. A work week seems like it took a day to pass while a co-worker next to you in the same age bracket feels like it took much longer.

    As you get near your 80's the gravity of the black hole starts tugging not only at your time harder by at you in physical ways. Your skin starts sagging, you break bones easier because of the greater gravity in the physical dimensions.. How many people have heard old people complain it's hard to walk?? Huh! Observable proof!

    Mercury clocks would help here. We attach one to every newborn for a decade and then look at the time distortion as it happens so we can figure out how to defeat this terror.

  • by spiffyman ( 949476 ) on Sunday July 16, 2006 @10:39AM (#15727950) Homepage
    I know I'm risking my own karma to ask this, but why was parent modded Redundant? The comment is funny, and it accurately illustrates why we might take time to do something seemingly useless. Because it might be useful, duh!

    Point is - parent should be modded up/funny. If I had mod points today I'd do it myself.
  • by John Nowak ( 872479 ) on Sunday July 16, 2006 @02:52PM (#15728837)
    They don't do that. Given a bank of 10 clocks, you'd have a 0.09765625% chance of them all losing time -- And then, not even at the same rate, so you'd not lose even a full second. Given a bank of 100 clocks, 7.8886090522101181e-29% percent. It's not really a problem.

e-credibility: the non-guaranteeable likelihood that the electronic data you're seeing is genuine rather than somebody's made-up crap. - Karl Lehenbauer