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New Atomic Clock 1000 Times More Accurate

CowboyNeal posted more than 9 years ago | from the chronographs-and-tickers dept.

Technology 313

stevelinton writes "The UK National Physical Laboratory has a new atomic clock potentially 1000 times more accurate than current cesium clocks: to within 1 second in about 30 billion years! This could lead quite soon to a new definition of the second, and in a while to improved resolution in GPS successor systems. More interestingly, there are theories that some of the universe's fundamental dimensionless constants may have changed by a parts in a million over the last 10 billion years or so. These clocks are so accurate that they should be able to detect these changes over a year or two."

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313 comments

I'll alert Britannica... (5, Funny)

grub (11606) | more than 9 years ago | (#10875215)


This could lead quite soon to a new definition of the second

Now all we need is a13 year old to update the wikipedia entry.

I love you grub. (0)

Anonymous Coward | more than 9 years ago | (#10875241)

But Wikipedia is objective! OBJECTIVE!!!

Re:I'll alert Britannica... (2, Funny)

bstadil (7110) | more than 9 years ago | (#10875314)

Now all we need is a13 year old to update the wikipedia entry

Hey! Wait a secon........never mind

Re:I'll alert Britannica... (0)

Anonymous Coward | more than 9 years ago | (#10875460)


teh wikeepeedeeah is teh shiznit. it halp me with my hoemwrk and maek me smarter than u, f4g.

Second Minute (5, Informative)

zenzic (804840) | more than 9 years ago | (#10875507)

According to Silvanus Thompson in his famous (and awesome!)(c1910) calculus book the word second comes from the term "second minute".

I thought that was a neat and strange word origin (if correct).

to quote him...
"When they came to require still smaller subdivisions of time, they divided each minute into 60 still smaller parts, which, in Queen Elizabeth's days, they called "second minutes" (i.e. small quantities of the second order of minuteness). Nowadays we call these small quantities of the second order of smallness "seconds"."

Is the warp drive working yet? (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10875222)

Ok, then. Wake me up when it is...

OMG FIRST COMMENT (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10875225)

WTF

Great! (0)

Anonymous Coward | more than 9 years ago | (#10875226)

Now, all we need is a device to create *more* time. In other words, slow down one's perception of time so one has more of it.

Re:Great! (2, Funny)

Orgazmus (761208) | more than 9 years ago | (#10875277)

Hehehehehe. *giggles*
You said time, man!

Re:Great! (0)

Anonymous Coward | more than 9 years ago | (#10875320)

(strained voice, as if speaking while trying to hold in one's breath)

LOL, u r teh funnay. *COUGH COUGH*

I'd mod you up, but I already commented in this article. Sorry.

Re:Great! (0)

Anonymous Coward | more than 9 years ago | (#10875297)

LOL, Get a little bit closer to c. 67,000 MPH just isn't enough to dilate time very noticibly.

Re:Great! (1)

fireboy1919 (257783) | more than 9 years ago | (#10875466)

Forget that.

I'm going to encorporate it into my time machine to lessen temporal drift.

Right now I have to make stopovers every twenty or so million years for temporal correction, which is a real pain (of course, this really depends on how accurate a time I'm looking for - am I looking to meet Greblok just a few years after I left him, or do I just want to watch dinosaurs?)

I figure I can maybe ramp it up to a billion with this. We'll see, though. Those atomic clocks weren't as good as I'd hoped.

Great! (5, Funny)

nixdorf_ (161552) | more than 9 years ago | (#10875233)

My boss will now know with 1000x the accuracy exactly how late I am. Wonderful!

Re:Great! (1)

willpall (632050) | more than 9 years ago | (#10875394)

I'm gonna assume that your boss was pretty accurate before, but now he will be so very precise!

Re:Great! (4, Informative)

metlin (258108) | more than 9 years ago | (#10875436)

No, he was right.

Accuracy is how close the measurement is to the actual value, precision is how much often the measurement is in agreement with the value.

Showing the wrong time, no matter how precise, doesn't mean much. The new clock is more accurate.

Wrist Watch? (1)

forkazoo (138186) | more than 9 years ago | (#10875240)

Having seen the atomic wrist watch linked fromthe article about the guy who recently made a chess set... I only consider this technology cool if you can wear it on your wrist!

Re:Wrist Watch? (2, Informative)

TeaQuaffer (809857) | more than 9 years ago | (#10875325)

The link of which you speek is here [leapsecond.com]

My favorite quote is "Batteries are included (they last about 45 minutes but are rechargeable)."

running late! (1, Funny)

Anonymous Coward | more than 9 years ago | (#10875243)

I am a billionth of a second late honey!

Re:running late! (2, Funny)

thepoch (698396) | more than 9 years ago | (#10875454)

You must be female. I hear it the other way...

"You're a billionth of a second late! Hmph!"

Damn clocks.

It's about time! (0, Offtopic)

Anonymous Coward | more than 9 years ago | (#10875245)

Sorry, couldn't resist.

Detecting cosmic temporal flatulence. (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10875246)

..when we can't even guarantee the essential postulates of our own science smells really
strange.

Atomic Clock Radio Accuracy (1)

linzeal (197905) | more than 9 years ago | (#10875263)

I love these units [amazon.com] I picked up at Fry's a while back and I wish my school was sensible enough to buy the wall units. Sometimes our wall clocks in the classrooms are hours off.

Re:Atomic Clock Radio Accuracy (1)

Ianoo (711633) | more than 9 years ago | (#10875407)

The light speed lag between you and the transmitter probably accounts for far greater "inaccuracy" than the actual atomic clock itself. Of course, we all know there's no such thing as "absolute time" (thanks, Albert), but it's interesting, nonetheless.

Re:Atomic Clock Radio Accuracy (1)

mOdQuArK! (87332) | more than 9 years ago | (#10875546)

Don't these clocks try and account for that, or even use the lag as part of their synchronization (kind of how the NTP daemon does)?

Accurate distance too? (4, Interesting)

Ckwop (707653) | more than 9 years ago | (#10875265)

Great.. now I can measure measure how late the train is to an accuracy of a few attoseconds. hehe

The great thing about getting more accurate timing is that it should allow you to measure distances with the same accuracy. I think that by shining two different coloured lasers against a mirror and measuring the beats in the interference pattern of the returned beam it should be possible to measure a metre very exactly.

Anyone know if this is garbage or does more accurate time mean more accurate distance.

Simon.

Re:Accurate distance too? (5, Insightful)

MasterC (70492) | more than 9 years ago | (#10875333)

The length of the meter is defined by time

http://physics.nist.gov/cuu/Units/meter.html

"The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second."

So if you can measure time more accuractly then you can measure a meter more accurately.

Re:Accurate distance too? (4, Insightful)

Mister Attack (95347) | more than 9 years ago | (#10875340)

The trouble with measuring a meter this way is that it's tricky, to say the least, to know the frequency of a laser beam to high enough precision for this to be a useful measurement. You'd basically have to do exactly what these guys are doing -- cool some ions to within a few microkelvins of zero, use them as a frequency reference and lock a laser to them. Then you'd have to do it again with a different frequency. Then you'd have to actually measure the intensity of the standing wave to high enough resolution that you could get a reasonable measurement. So basically, don't hold your breath.

Much more reasonable is to keep the current definition of the meter, which is the distance that light travels in 1/299,792,458 second in a vacuum. Then your better clock gives you a more accurate length standard without all the fuss.

Re:Accurate distance too? (4, Funny)

bobdotorg (598873) | more than 9 years ago | (#10875366)

it should be possible to measure a metre very exactly.

Ah - but I suspect that measurement of what comprises six inches will be as imprecise and inaccurate as it's always been.

I am (0)

Anonymous Coward | more than 9 years ago | (#10875269)

already perceiving time faster, as I get older. Unlike previous generations, w/ each incarnation humans are perceptually faster [generally]; unless of course you're just stupid... which sadly most people are heh :P

Why do this? (2, Interesting)

zerman (832210) | more than 9 years ago | (#10875272)

I don't mean to be offensive, but is there any real point to this? How much accurate does the clock really have to be? What is the point of having a clock that is this accurate? We pour millions of dollars into this type of thing. So what? Even if we did need the accuracy (which we don't) we would never have it because the accuracy bottleneck would always be transporting the signal to wherever it's needed. Can anyone think of one good example where this clock serves any real purpose, and the old cesium one wasn't good enough?

Re:Why do this? (3, Informative)

Lisandro (799651) | more than 9 years ago | (#10875294)

It won't be of any use to the regular Joe. But there's a lot of scientific experiments that rely on accurate time measurements, notably those involving relativistic effects.

Re:Why do this? (1)

zerman (832210) | more than 9 years ago | (#10875316)

Okay, I'll accept that. But won't there be inherent inaccuracy in any cables or anything like that that would carry this signal? How are they going to get the signal from the clock to where it's needed?
You get what I mean?

Re:Why do this? (1)

stevelinton (4044) | more than 9 years ago | (#10875328)

What you get are a series of (say) laser pulses whose intervals are extremely regular, or a single laser source whose frequency is extremely steady. So long as you carry them all on the same path, you won't lose that regularity. The pulse (or laser wavecrest) a year later will be within 10 picoseconds of exactly when it is supposed to be, in relation to the one a year earlier.

Re:Why do this? (1)

RWerp (798951) | more than 9 years ago | (#10875537)

So long as you carry them all on the same path, you won't lose that regularity.

This is the non-trivial part. Light fibres can carry one pulse faster than other, because the fibre can change its shape a little bit over time.

Re:Why do this? (1)

Bombcar (16057) | more than 9 years ago | (#10875301)

Well, if it is accurate enough to detect minute changes in physical constants, then it will be worth it, as it will give us better understanding of the universe around us.

And it allows the UKians to brag, and also detect the end of a soccer match with much more accuracy.

Re:Why do this? (0)

Anonymous Coward | more than 9 years ago | (#10875378)

Don't need it for that. Alex Ferguson has his stopwatch.

Re:Why do this? (0)

Anonymous Coward | more than 9 years ago | (#10875412)

I think you mean football. :-)

Yes. (1, Redundant)

DAldredge (2353) | more than 9 years ago | (#10875306)

More interestingly, there are theories that some of the universe's fundamental dimensionless constants may have changed by a parts in a million over the last 10 billion years or so. These clocks are so accurate that they should be able to detect these changes over a year or two."

Re:Why do this? (2)

Carthag (643047) | more than 9 years ago | (#10875307)

I don't mean to be offensive, but is there any real point to this?
"This could lead quite soon to a new definition of the second, and in a while to improved resolution in GPS successor systems. More interestingly, there are theories that some of the universe's fundamental dimensionless constants may have changed by a parts in a million over the last 10 billion years or so. These clocks are so accurate that they should be able to detect these changes over a year or two."

Re:Why do this? (4, Informative)

stevelinton (4044) | more than 9 years ago | (#10875318)

The accuracy of caesium clocks is one of the factors limiting GPS accuracy to a meter or so. These clocks could get that down to a millimeter allowing, for instance, GPS based automated guidance for trucks and automated landing for planes.

There are also applications in scientific research -- I mentioned detecting changes in fundmental constants in the story, it might also help allow very long baseline interferometry (where two radio telescopes thousands of miles apart obtain the same resolution as one telescope thousands of miles wide) at higher frequencies, pushing into the long IR.

Let's not forget this App (0)

Anonymous Coward | more than 9 years ago | (#10875348)

These clocks could get that down to a millimeter allowing, for instance, GPS based automated guidance for trucks and automated landing for planes.
This will also allow the military to bomb the wrong targets much more accurately.

Re:Why do this? (4, Interesting)

maeka (518272) | more than 9 years ago | (#10875432)

The accuracy of the clocks is a small factor in real-time GPS accuracy.

Ionospheric delay plays a much larger role. Survey-grade receivers use both the L1 and the L2 bands in an attempt to better model this delay. Ionospheric delay is frequency-dependent and impacts on the L1 and L2 signals by a differing amounts.

Multipath plays a role also, not as big as the ionosphere, but still larger than the accuracy of the clocks on the GPS satellites.

Re:Why do this? (1)

Lumpy (12016) | more than 9 years ago | (#10875445)

I find errors in the datasets larger than the GPS positioning error.

computer guided trucks, the horrible idea consideringthe horrible accuracy of the gurrent GPS dataset's available. no not the low grade Delorme maps for US Census data... I'm talking the high priced stuff from the company navtek that claims the highest accuracy possible. (yet missing most data, having roads where they do not exist and having the position of an entire highway off by over 500 meters.

if we cant get good data to begin with, super hiigh accuracy GPS will do nothing for us.

Re:Why do this? (0)

Anonymous Coward | more than 9 years ago | (#10875526)

These clocks could get that down to a millimeter allowing, for instance, GPS based automated guidance for trucks and automated landing for planes.

We already have a safe and reliable autolanding system, there is no need to switch to a gps-based system. Airports with an ILS Cat. 3C system are certified to autoland aircraft in 0ft visibility.

Re:Why do this? (0)

Anonymous Coward | more than 9 years ago | (#10875415)

Translation: Who gives a fuck!?!?!!?!?!?!?!?!??!?

Re:Why do this? (2)

Sai Babu (827212) | more than 9 years ago | (#10875440)

"A second highly-monochromatic red laser (674 nm) is then aimed at the cold ion, and tuned to two very precisely defined energy states in the cold ion. Once the laser is locked on to this precise energy or frequency interval it becomes very stable."

ASIDE: Strontium give the nice red you see in fireworks.

Physical constants are defined in terms of time. We only know that they are constants so far as we can measure the passage of time. Our model of the universe is based on constancy. With a better clock we can refine or if necessary change the model.

If you care to learn about time, take a tour of the Navel Observatory's Time Service Department. [navy.mil]

Re:Why do this? (5, Interesting)

Misanthropy (31291) | more than 9 years ago | (#10875481)

I was thinking the same thing until I actually read the article.

An answer from the article that affects everyone and not just super geek physicists:

Navigation on earth - based on a cluster of orbiting satellites - is limited by the accuracy of the atomic clock on each satellite. A series of calculations can get millimetre accuracy on the position of a stationary object, but for moving objects like cars and planes the accuracy is no better than a few metres. Only by making faster measurements can this accuracy be improved, something enabled by a more accurate definition of the second.
...
"That is why GPS is not yet good enough to land a passenger aircraft on its own," Prof Gill says.


Pretty cool stuff.

Give or take a year... (2, Funny)

CleverNickedName (644160) | more than 9 years ago | (#10875300)

More interestingly, there are theories that some of the universe's fundamental dimensionless constants may have changed by a parts in a million over the last 10 billion years or so. These clocks are so accurate that they should be able to detect these changes over a year or two.

Exactly how long will it take to detect these changes?

Re:Give or take a year... (1)

snellgrove2 (724957) | more than 9 years ago | (#10875343)

well, I suppose it depends on which constant.. different ones change at different rates, no doubt

and it also depends whats happening in the universe, I guess.

but thats only what im presuming, I dont know for sure, and I havent RTFA!

Why go any further (2, Interesting)

suso (153703) | more than 9 years ago | (#10875327)

1 second every 30 billion years? That's more than twice as long as the age of the universe. So why then would atomic clock developers need to go any further?

Re:Why go any further (4, Informative)

stevelinton (4044) | more than 9 years ago | (#10875341)

Because they're interested in deviations of much less than a second.

Re:Why go any further (1)

suso (153703) | more than 9 years ago | (#10875482)

Really? Because when they say "loses one second every billion years", it sounds like they are using it to keep time.

For what its worth, I understand tht atomic clocks are more used for minute time measurement than keeping time. But I wish they would say something like "accurate to a nano-second" or whatever.

Re:Why go any further (2, Interesting)

metlin (258108) | more than 9 years ago | (#10875398)

Because you need precise measurements for things other than needing to know what the time is.

And these clocks are not just used as solar clocks, they are calibrated to be sidereal clocks too - to know the movement of the stars and the like.

Imagine you are conducting a particle collision experiment in a tunnel - the particles are almost travelling at the speed of light, and they'd cover the distance of your tunnel almost instantaneously. You would need to measure this as precisely as you can. The more this measurement is, the more precisely we can calculate how the data from other particle collisions in the Universe (from cosmic rays, for instance) are - letting us know how the Universe has changed/is changing.

There are several applications of it - most of it of interest to physicists only, ofcourse.

Like Henry Ford said when visiting a museum (4, Funny)

melted (227442) | more than 9 years ago | (#10875336)

of clocks: "I see no progress in this industry. These clocks are no faster than the ones they made a hundred years ago."

Faster Networks? (1)

retostamm (91978) | more than 9 years ago | (#10875358)

I understand that in some types of backbone network connections, a pair of Atomic Clocks is synchronized, then one is sent to each end of the connection.

Will it be possible to run these connections at a higher speed with more accurate clocks?

Not really new (4, Informative)

Dolphinzilla (199489) | more than 9 years ago | (#10875362)

trapped ion frequency standards are nothing new, NIST made one years ago, the only difference is that NPL uses Strontium instead of Mercury. While it appears to be more accurate than the NIST one, trapped ion standards are not very practical to build or run for everyday use and its not a primary frequency standard, since the definition of the second is in terms of Cesium resonance, only Cesium clocks are primary frequency standards.

Re:Not really new (1)

fatphil (181876) | more than 9 years ago | (#10875509)

You seem to be forgetting the fact that all these standards are arbitrary, and could be changed at a committee's whim.

It's happened before, and it will happen again.

For example, thanks to committees pounds are metric units of mass. Yup - pounds are metric.

FP.

Re:Not really new (1)

stevelinton (4044) | more than 9 years ago | (#10875531)

They claim that this setup is simpler than the NIST one, as well as 3 times more accurate.

It also seems to be understood that once some sort of optical resonance technique becomes established, the second will be redefined in terms of it.

Steve

That's nice but... (4, Funny)

ZoneGray (168419) | more than 9 years ago | (#10875364)

That's all well and good, but I'll bet it still flashes "12:00-12:00-12:00" after the power goes off.

Re:That's nice but... (0)

Anonymous Coward | more than 9 years ago | (#10875489)

> That's all well and good, but I'll bet it still flashes "12:00-12:00-12:00" after the power goes off.

Let me break this down of you, OK?

1. A clock needs energy to function (aka. power)
2. Now lets turn the hypothetical power/energy off (you following so far?)
3. What do you think happens here, "after the power goes off"?

You get a star if you can work it out

Re:That's nice but... (1)

ZoneGray (168419) | more than 9 years ago | (#10875544)

What do you think happens here, "after the power goes off"?

Ummm, I know:
1 - Smartass grammar geek figures it's safe to stick his finger in the socket.
2 - Power comes back on.
3 - Clock flashes "12:00-12:00-12:00"
4 - grammar geek says nothing.

;)

Ironic it's from the UK (-1, Redundant)

Teun (17872) | more than 9 years ago | (#10875371)

UTC is the world-wide standard for time.

The UK hosts the 0 Meridian, the home of the Universal Time Coordinate.
Yet the UK is mostly on Greenwich Mean Time (GMT), a sytem that is typically something like a whole second off with UTC...

Why the Fu** are they investing in "a 1000 times more accurate"?

Re:Ironic it's from the UK (0)

Anonymous Coward | more than 9 years ago | (#10875523)

Wrong on all counts, I'm afraid.

GMT is calculated from the mean position of the sun with regards to the 0 meridian, so it is the home of GMT, not UTC.

UTC is taken from atomic clocks, and is defined as never being more than .9 seconds off GMT. Whenever it drifts outside of this range, a leap second is either added or subtracted from UTC.

The reason? GMT is more useful from a practical point of view - atomic clocks are more accurate than the Earths' orbit, and so will drift off the actual calendar day.

this might be a stupid question but... (1)

d4n (817192) | more than 9 years ago | (#10875376)

how do we know how accurate it is? The thing is, the amount of time the earth takes to go round the sun varies ever so slightly, as does the amount of time it takes the earth to rotate on it's axis. So what exactly are we measuring this new clock against in order to determine its accuracy? Surely, in order to dermine that it is accurate down to 1 second off over 30 bln years, we must be using some other more accurate measure that isn't off by 1 second over 30 bln years (say for example the amount of time it takes light to travel 3mx10^8 in a vacuum), so why don't we just continue using that more accurate measure?

Re:this might be a stupid question but... (1)

PeteGT (685127) | more than 9 years ago | (#10875421)

Good point. Since we are looking at approximating the time it takes to go around the sun, then it does lend to a question upon why or how something is more "accurate"? Isn't the time we look at arbitrary? We say the one second is this because WE say it is. Just as one minute is 60 seconds. Even months and years really are just arbitrary units. I'm posing more of a question, not disputing this article.

Re:this might be a stupid question but... (1)

zerman (832210) | more than 9 years ago | (#10875439)

I don't think we are measuring it against the earth moving around the sun. Rather, we are measuring it by the strict physical definition of a second, which has nothing to do with celestial bodies.

Re:this might be a stupid question but... (1)

d4n (817192) | more than 9 years ago | (#10875463)

Yeah but that's my point, what is the strict physical measure of a second and why don't we build clocks that measure that instead of inventing clocks that aren't quite right?

Re:this might be a stupid question but... (1)

sam_da_mann (758118) | more than 9 years ago | (#10875512)

The international unit of the second is defined as "the duration of 9,192,631,770 cycles of microwave light absorbed or emitted by the hyperfine transition of cesium-133 atoms in their ground state undisturbed by external fields"

Changes in Constants? (4, Informative)

TeaQuaffer (809857) | more than 9 years ago | (#10875380)

There is a little blip by Chris Carilli [physicsweb.org] about changes in constants. [SIC] and more detailed article here [physicsweb.org] .

Does anyone know more about this?

Re:Changes in Constants? (1)

azaris (699901) | more than 9 years ago | (#10875464)

Constants that change? That's nothing new.

Anyone who's done some programming knows that constants aren't and variables don't.

does this mean..... (0)

Anonymous Coward | more than 9 years ago | (#10875386)

that i'm really older or younger than i am? and it's quite possible that the poop i just took took less time than i thought it did?

I should get one of these... (1)

Misanthropy (31291) | more than 9 years ago | (#10875396)

...and maybe I could get up on time.
My quartz clock made me a 1/4 second late to class the other day!

Sure everybody says, "why don't you just get up a quarter second earlier?"
Well, easier said than done!

fundamental constants? (1)

osho_gg (652984) | more than 9 years ago | (#10875437)

"More interestingly, there are theories that some of the universe's fundamental dimensionless constants may have changed by a parts in a million over the last 10 billion years or so. These clocks are so accurate that they should be able to detect these changes over a year or two"

If these constants change over a year or two, they are not so fundamental right?

Osho

Re:fundamental constants? (1)

Zen Punk (785385) | more than 9 years ago | (#10875542)

I'm sure they are, but I guess they are not so constant. Perhaps they should be called fundamental variables?

Re:fundamental constants? (2, Funny)

Stevyn (691306) | more than 9 years ago | (#10875560)

so I guess seconds should be represented as floats instead of ints?

Bad reporting (5, Informative)

fatphil (181876) | more than 9 years ago | (#10875461)

Slashdot's error -
It's not 1000 times more accurate, it's 3 times more accurate (than the NIST's mercury ion resonator). The figure of 1000 is what they think the technology in the future, but that's purely hypothetical.

NPL's errors -
Bombarding an ion with a blue laser in order to cool it is _in_no_way_ similar to firing a beam of light at a mirror-ball. Mirror balls do not get cooler when you fire beams of light at them. Explanations that use inappropriate analogies are as useful as wearing tie-died lab-coats in night-clubs.

If "one part in 10^18" is "nearly a thousand times more accurate than the best clocks of today", then today's best clocks must be accurate to 1 part in 10^15. Therefore this new clock, being "three times more accurate than the Americans", "3.4 parts in 10^15", cannot be the be the best clock of today. Either that or someone in NPL can't do simple maths.

FP.

Cesium beam clock old tech (1)

shipkiller (155095) | more than 9 years ago | (#10875471)

Cesium beam clocks are old tech. U.S. Naval Obeservatory (the US time standard) and the US Military use Rubidium Beam clocks. Smaller, and much more accurate.

According to the USNO's site... (1)

theurge14 (820596) | more than 9 years ago | (#10875535)

" The atomic clock timescale of the Observatory is based on an ensemble of approximately 50 cesium-beam frequency standards and a dozen hydrogen masers. Frequency data from this ensemble are used to steer the frequency of another such maser, designated Master Clock 2 (MC #2), until its time equals the average of the ensemble, thereby providing the physical realization of this "paper timescale." Specifically, the frequency of a device called an Auxiliary Output Generator is periodically adjusted so as to keep the time of this maser synchronized as closely as possible with that of the computed mean timescale USNO timescale UTC (USNO), which in turn adjusted to be close to the predicted UTC (BIPM). The unsteered internal reference timescale is designated as A.1, while the reference of the actual Master Clock is called UTC (USNO). UTC (USNO) is usually kept within 10 nanoseconds of UTC (BIPM). An estimate of the slowly changing difference UTC (BIPM) - UTC (USNO,MC #2) is computed daily." http://tycho.usno.navy.mil/master.html

Time is relative (0)

Anonymous Coward | more than 9 years ago | (#10875473)

stevelinton writes "The UK National Physical Laboratory has a new atomic clock potentially 1000 times more accurate than current cesium clocks: to within 1 second in about 30 billion years! This could lead

All it would take is a little shift in gravity or the rate the world turns... time is relative. If time were a constant the sun would flare up and die out quite quickly.

I wonder if the therorists factored this into the expanding universe theory as the earth's mass isn't constant either which affect all our observations over time.

Write this off as hype science.

How do they know? (1)

FooBarWidget (556006) | more than 9 years ago | (#10875479)

How do they know it's more accurate than cesium clocks? You need to compare this new clock to something else in order to tell whether it's more accurate. But how do they know this clock is more accurate, if they don't have something which is already 100.0% accurate?

Re:How do they know? (1)

stevelinton (4044) | more than 9 years ago | (#10875547)

What they really mean is more stable. If you compare a bunch of cesium clocks, or compare one cesium clock now with its behaviour at a different time (having bounced the signal off the moon or something) you get a random variation of (with the very best cesium clocks) about 1 part in 10^15. With these clocks, they expect to be able to get this variation down to 1 in 10^18 over the next few years.

Moving accurate time around is more important! (0)

Anonymous Coward | more than 9 years ago | (#10875491)

So what? Someone developed a clock that is super-accurate. But my telephone company, local TV station, and bus service still don't know anything about clock accuracy.

As seen on this blog [blogspot.com] and here [weblogs.com] , people who run time services don't even know how to implement NTP!

Sorry, obSimpsons quote (1)

whterbt (211035) | more than 9 years ago | (#10875499)

More interestingly, there are theories that some of the universe's fundamental dimensionless constants may have changed by a parts in a million over the last 10 billion years or so.

PI IS EXACTLY THREE!
-Prof. Frink

damn whippersnappers (1, Funny)

Anonymous Coward | more than 9 years ago | (#10875506)

When I first started timing things we used plain 'ol rubidium clocks..and WE LIKED IT!!

Awesome (5, Funny)

roman_mir (125474) | more than 9 years ago | (#10875552)

But the real question is can MS make a download status bar that is 1000 times more precise and does not go from 2 minutes to 20, then to 4 minutes, then to 5 minutes etc. Or this invention does not affect a standard Microsoft Millisecond (which I believe is a random function?)

My Brain Just Exploded (1)

unknown51a (741797) | more than 9 years ago | (#10875553)

My brain just exploded in the effort it was taking trying to understand how to redefine something that only exists because of its definition... Could someone help me pick up the pieces.

Bah. (1)

danila (69889) | more than 9 years ago | (#10875561)

I didn't have time to RTFA, but I don't think anyone would use it - it was proven time and time again, that inventors and tinkerers are so ahead of their time. :(
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