Haha
"This is a milestone for atomic clocks" .......... classic !!!
US government boffins say they have built a clock so precise that it will still be accurate to within one second when life on Earth has ceased. The "quantum logic clock" will neither gain nor lose a second over the next 3.7 billion years, according to its makers at the US National Institute of Standards and Technology (NIST). …
If the second is *defined* by the Caesium atomic clock, and this new clock will disagree with a Caesium atomic clock after only 100 million years, then this new clock is surely less accurate, by definition?
So we'll have to redefine what a second *is* in order for this clock to become more accurate.
Well if we can redefine a second to be whatever we like then I declare my watch to be the standard, and thus the most accurate clock on Earth.
"Chou's clock will quite literally be the only one we'll ever need - a veritable doomsday clock."
Call me selfish, but one that will last out the remainder of this century will be more than enough for my purposes...
In fact this one is more than I need
http://www.longnow.org/clock/
I dunno, but I imagine you could build several and measure their growing disagreement with each other and calibrate those measurements against your trusty sundial (or Caesium clock if you have one).
The problem doesn't sound *very* different from estimating the mean-time between failures for hard-drives. Come to think of it, neither are the answers. Don't hard drives claim to last billions of years these days? (On average, I mean. Obviously not in *your* PC.)
Rubidium atomic clocks on board the satellites provide the time reference for the GPS system. obviously an upgrade to these for the next generation (or Gallileo) would tighten up the whole systems accuracy.
However this one's likely to be pretty bulky. An experimental JPL unit uses a few mercury atoms and is IIRC 1000x more accurate than the GPS clocks while only taking up 2litres of volume (and of course standing a full space launch). Handy if you want launch a satellite constellation into relatively high (800-1000Km) low earth orbit.
Note that atomic clocks are not normally viewed as portable. More 20 ft container sized than desktop. Making most of the vacuum system in 1 piece out of materials that can take a 450c bakeout (gas molecules desorbing off the walls contaminate the signal) seem to have been key elements.
Quote: 'While the Sun should have some time to run before becoming a red giant - and so engulfing the Earth and much of the solar system'.
If I remember correctly, the Earths orbit, like all the planets, is slowing down, therefore slowly drifting away from the Sun. By the time our Sun becomes a red giant, we'd be far enough away not to be engulfed by the Sun. (Although the planet would still be dead by then anyway, so still not exactly good news!).
Plus our Sun won't turn into a Red Giant for about another 5.4 billion years or so, so the clock could actually be out by over a second by then ;-)
More than 99% of all species of animal ever to have lived on earth is now extinct. Human's are the only species of animal capable of stopping themselves from going extinct and yet are the only animal on the planet wilfully hastening their own demise. It is extremely unlikely that by the time the sun starts the process or achieving red giant status any humans will be around to care.
Most likely is that humans will be wiped out or continue wiping themselves out. Causing the earth to repair it's natural resources for a few million of years paving the way for new species of animal any of which may or may not become equally or more intelligent than the humans who lived in the ancient past to rule the earth. Rinse and repeat the cycle for a few billion years until the great red fireball in the sky finally burns the planet to a cinder.
..probably something like that anyway?
Quantum physics being the cranky thing that it is, what if that vital atom decides to spontaneously flip into another universe, or otherwise disappear up its own a*se? I hope they have a spare, although then, as Confucious was wont to remark:
"Man with one clock know exactly what time it is. Man with two clocks never quite sure".
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OK, if the pedants are having a go at the definition of "second", I'd like to point out that a 'clock' is a chronograph which has bells on.
If there are no bells (or whistles, or other alarm or striking mechanism) it is merely a 'timepiece'. No indication of any bells on this new-fangled quantum chronograph.
(My father is a horologist).
Of course this accurate clock is nonsense it is just a bragging rights. In truth the earth clock is not accurate, it is slowed by tidal forces. 700m years ago the day was only 17hours long (or correctly the hour was 17/24 of what it is now). In the future the earth will become tide locked first with the moon then eventually with the sun. Just imagine an 8760hour year. There will be no living with that. So what is the point of an accurate clock ?
All this is supposed to happen a long time in the future. But is it? If we take energy out of the earth by using tidal generation then it will be sooner and it is not reversible. We have no idea of the impact of further slowing of rotation. I think it will make global warming seem like a walk in the park.
Scared? You should be and it is coming to an ocean or sea near you.