New Atomic Clock Could Redefine the Second

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New Atomic Clock Could Redefine the Second

Posted by Soulskill on Tuesday July 9, 2013 @09:37AM from the about-time dept.

bmahersciwriter writes "The new type of clock, called an optical lattice clock could replace the cesium fountain clocks used as the standard for time keeping. Indeed, it could redefine the second. The cesium fountain is predicted to keep time within one second over 100 million years. While other atomic clocks are better than that, researchers suspect the optical lattice is better still and could one day replace the standard."

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I want to redefine the second by Skapare · 2013-07-09 09:41 · Score: 4, Funny

... as 1/65536 of a day. Then I can do time calculations on my 6502.

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1. Re:I want to redefine the second by turgid · 2013-07-09 10:14 · Score: 1
  
  Ah now, back in the day, the IBM PeeCee (which had an 8088) kept time at a rate of 65536 ticks per hour. How this divides into a second is left as an exercise for the interested reader.
  The second question for the interested reader is how on Earth anyone could achieve any sort of calculation at all on a 6502 what with it being quite the most pathetic excuse for a CPU ever devised by person-kind.
  
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2. Re:I want to redefine the second by Goaway · 2013-07-09 10:34 · Score: 2
  
  While you are sitting around complaining, REAL MEN are making it do things like http://www.youtube.com/watch?v=oBegD7k2wvo.
3. Re:I want to redefine the second by BitterOak · 2013-07-09 10:35 · Score: 2
  
  The second question for the interested reader is how on Earth anyone could achieve any sort of calculation at all on a 6502 what with it being quite the most pathetic excuse for a CPU ever devised by person-kind.
  I hope you're kidding. The 6502 helped make the personal computer revolution possible. For a time, it was the lowest price workable 8-bit CPU available, making computing available to the masses. The original Atari game console (the 2600) was based on the 6502, as was the Apple II computer, which really launched the small computer revolution, and the 6510 (a slightly enhanced version of the chip) powered the extremely popular Commodore 64 computer. True, pricier CPUs like the Z-80 and others were a bit more capable, but it was the 6502 that really made home computers affordable in the early days.
  
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4. Re:I want to redefine the second by PRMan · 2013-07-09 10:56 · Score: 1
  
  Actually, the Atari 2600 had a 6507, which, if you can believe it, was WORSE than a 6502.
  
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5. Re:I want to redefine the second by petermgreen · 2013-07-09 11:26 · Score: 1
  
  IIRC the NES CPU lacks some features that the regular 6502 has (BCD mode comes to mind).
  
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6. Re:I want to redefine the second by mrmeval · 2013-07-09 11:43 · Score: 1
  
  Nope, a second is the time it takes for a politician to determine they need to steal more of your money for the good of the government. It keeps getting shorter.
  
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7. Re:I want to redefine the second by Charliemopps · 2013-07-09 12:19 · Score: 1
  
  My first computer was a Vic-20 (6502) and I wrote my first program on that when I was about 7 using a book my dad got me. I had the cassette tape drive, a modem (with no-where to call) some cartridges. Man, I thought that thing was magic. My friends had Atari's and stuff, but I could actually make my computer do stuff...
Yeah, that's what they said by ackthpt · 2013-07-09 09:41 · Score: 4, Funny

a second ago...

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1. Re:Yeah, that's what they said by LongearedBat · 2013-07-09 20:53 · Score: 1
  
  The definition of "a second" ago keeps changing. Please try to be more precise.
When better isn't better by Dan+East · 2013-07-09 09:41 · Score: 2, Interesting

While other atomic clocks are better than that, researchers suspect the optical lattice is better still and could one day replace the standard.
So A is better than B, but B is still better than A. Makes sense.

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1. Re:When better isn't better by GodInHell · 2013-07-09 09:46 · Score: 4, Informative
  
  So A is better than B, but B is still better than A. Makes sense.
  No. The summary says:
  
  The cesium fountain is predicted to keep time within one second over 100 million years. While other atomic clocks are better than that, researchers suspect the optical lattice is better still and could one day replace the standard.
  Thus: where A = Optical lattice, B= Cesium fountain (the standard), and C = other atomic clocks; A > B; C > B; A > C
2. Re:When better isn't better by icebike · 2013-07-09 09:50 · Score: 1
  
  The Current STANDARD Atomic Clock (a) is already surpassed by other Atomic Clocks (b) but the new Optical Latice (c) is better still.
  I had to do a double take as well.
  
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3. Re:When better isn't better by Roman+Coder · 2013-07-09 09:59 · Score: 1
  
  A > B; C > B; A > C
  And here I thought it meant that both A and C attacks B, then A gets mad at C for killstealing and attacks C.
  
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  "The future can only affect the present if there is room to write its influence off as a mistake." - Yakir Aharonov
4. Re:When better isn't better by jfengel · 2013-07-09 09:59 · Score: 1
  
  It took me a couple of extra readings, too. The tricky unstated part: while other atomic clocks are better than cesium clocks, they are not the standard.
  TFA doesn't explain why trapped-ion clocks (the "better clocks" mentioned in TFS) aren't used to define the standard. Presumably, that's just the glacial pace of international standards setting, and perhaps a trapped-ion clock standard is working its way through the system but has not yet become the new standard. That's just my guess, though.
5. Re:When better isn't better by hedwards · 2013-07-09 10:03 · Score: 1
  
  The better clocks would have to be sufficiently better to justify the change. The current cesium fountain clocks are accurate to about 1 second in a hundred million years. There are better ones, but it's difficult to improve much upon that, at least not sufficiently to justify the change.
  Which is what I suspect is going on here. The current clock is likely to already be more accurate than the means of conveying the standard to other time keeping devices.
6. Re:When better isn't better by icebike · 2013-07-09 10:55 · Score: 1
  
  B is still better than A when it's simpler/less expensive to produce and is already the adopted standard.
  So no improvement can be made because someone adopted a standard?
  The horse an buggy was a standard for a long time.
  
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7. Re:When better isn't better by grantspassalan · 2013-07-09 12:20 · Score: 1, Interesting
  
  Behind all this accuracy is on the assumption that the atomic constants, such as Planck's "constant" are truly constant, because all atomic behavior is governed by this. There is evidence that for long periods of time these so-called "constants" have drifted and still are drifting, because they are related to the size of the universe. All the equations for atomic behavior contain a time element as part of these so-called "constants". The equations for gravity on the other hand to not contain any terms referring to time. Gravity clocks and atomic clocks to not run at the same rate, especially over long periods of time. Therefore the supposed of accuracy of these and all atomic clocks is an academic exercise based on faith.
  
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8. Re:When better isn't better by Anonymous Coward · 2013-07-09 14:14 · Score: 2, Informative
  
  There is evidence that for long periods of time these so-called "constants" have drifted and still are drifting, because they are related to the size of the universe
  There is no good evidence of that and a lot of evidence to the contrary, everywhere from astrophysical data to on going work in the labs. And it is not like everyone is assuming so, people are actually checking and running experiments from such things. I've seen some of them first hand considering former colleagues of mine ended up on such a project.
  
  The equations for gravity on the other hand to not contain any terms referring to time.
  
  Then you must be about 100 years behind the times, as gravity is closely tied to the rate of time passage, both in theory and thoroughly demonstrated by experiment.
  Everything you said is so close to the exact opposite of current physics research (or even intro level physics), that it would be difficult to believe you are not a troll.
9. Re:When better isn't better by DMUTPeregrine · 2013-07-09 14:57 · Score: 2
  
  Cesium fountain clocks last about 20 years, some a bit longer, before they need to get parts replaced for maintenance. The standard is transferred to a backup during this time, then transferred back. Improving on the lifetime of the individual clocks would help more than improving on the accuracy of the clocks.
  
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10. Re:When better isn't better by AmiMoJo · 2013-07-09 22:43 · Score: 1
  
  Pfffff... My 1985 vintage Casio is still going and keeps perfect time. Obviously we should use an 80s vintage digital watch as our master reference.
  
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11. Re:When better isn't better by icebike · 2013-07-10 08:50 · Score: 1
  
  Total nonsense.
  There will be no redefinition of the second, it will be precisely as long as it is today.
  We will simply change the ruler with which we measure a second.
  Defining a meter as 100 centimeters, or 1000 millimeters, or 10,000,000,000 angstroms, or 3.281 feet does not change the length of a meter.
  
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sorry, i don't have time for this by NemoinSpace · 2013-07-09 09:41 · Score: 5, Funny

My watch is made in china.
1. Re:sorry, i don't have time for this by thegarbz · 2013-07-09 22:32 · Score: 1
  
  Funny you should mention that. The average quartz based Romex is likely to be more accurate than the officially certified chronometer that it's ripping off.
  The only problem is the second hand only goes around the dial 100 times before it falls off, but for those 60 hours it'll be more accurate than a Rolex.
So, now we need not just leap seconds... by ChumpusRex2003 · 2013-07-09 09:45 · Score: 1

but leap microseconds?
Actually, I think that might be a good idea. There's likely to be money in rewriting time stacks to cope with 1000001 microsecond seconds.
Re:About time for the frist post by fisted · 2013-07-09 09:45 · Score: 1

oh sh--

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so what? by WillgasM · 2013-07-09 09:47 · Score: 4, Funny

It's still relative.
Happy times by jovius · 2013-07-09 09:51 · Score: 5, Funny

Yeah, no more sloppy seconds!
1. Re:Happy times by aliquis · 2013-07-10 07:18 · Score: 1
  
  "You only lasted four seconds!"
  "Sorry but your watch are like totally wrong!"
Grumble.. by SinisterRainbow · 2013-07-09 09:51 · Score: 1

Just when you start to think you know everything you read something and fail to grasp it's significance and feel dumb or naive all over again.

Well, then you just hope it helps make a warp core.

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1. Re:Grumble.. by centipedes.in.my.vag · 2013-07-09 10:07 · Score: 1
  
  The more exact and finite an objective standard of time we posses the better we can measure other things. More lines on a 4th dimensional ruler, if you will.
  
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2. Re:Grumble.. by SinisterRainbow · 2013-07-09 11:55 · Score: 1
  
  That's not what I meant, but kind replies are always nice. I understand the function, but just like most of us don't spend our off hours learning string theory and pondering just how small plank's constant is (at least, rarely), I doubt many of us keep abreast of experiments that use this type of precision or what truly interesting things that will come of it - at LEAST what truly interesting things that justify the seemingly inflated giddiness of the article.. Hence my dissatisfaction.
  
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  -Ultimate Stickman Game Developer Infinite World Puzzler
Exceptionally poorly written summary. by Jahoda · 2013-07-09 09:55 · Score: 1

Look, not for nothing, but this summary really is exceptionally poorly written. "...while other atomic clocks are better than that, researchers suspect the optical lattice is better still..."? Is this the 10th grade? "Better than that" is how we summarize a new type of clock? Why don't we just throw style out the window and write that it's very, very, very, very, very, very, very good? Additionally, can we possibly have even a quick sentence to explain of why the optical lattice is "better still"?. I mean, I can obviously read the article, but frankly now I don't want to.
Ah, time by sixsixtysix · 2013-07-09 10:05 · Score: 1

Ah, time. Man's cruelest construct.

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Well.. by deep44 · 2013-07-09 10:08 · Score: 4, Funny

All I can say is.. it's about time!
A new summary by bryanandaimee · 2013-07-09 10:16 · Score: 5, Informative

The new (less than a decade old) optical latice clocks (OLC's) in which 10,000 atoms of strontium-87 are trapped in (what else) an optical lattice have been shown to be better (within 1.5x10^-16) than the current world standard cesium fountain clocks (within 3x10^-16), but haven't yet beat the best clocks, which are measuring emissions from single ions trapped in an electro-magnetic field (within 1x10^-17). But researchers are hopeful that OLC's will eventually emerge as the new standard because 10,000 atoms beat 1 atom for measurement statistics and because the other two technologies measure frequencies in the microwave spectrum, while the optical lattice clock is measuring in the visible spectrum. Statistics and higher frequencies should eventually win out as the technology matures.
1. Re:A new summary by E3nder · 2013-07-09 12:38 · Score: 2
  
  Ion clocks are also based on optical transitions. So your new summary is incorrect. Also, it's not really "statistics" that win out, its the ability to probe your ensemble (either 1 ion or many atoms) with lower Quantum Projection Noise. For example, everytime your laser has excited your ion to a quantum superposition of ground and excited state all you get back is one bit of information: 1 - excited state, 0 - ground state. So to discover where your laser (aka clock oscillator) is detuned with respect to your atomic reference or in another words what quantum superposition you created requires you to run the experiment many times. With an optical lattice clock, you gain the ability to measure more than just a 1 or a 0, you measure as an example 2035 atoms in the excited state and 812 atoms in the ground state or an excitation fraction of 0.714. It is statistics, but it's quantum in nature.
2. Re:A new summary by hyperfine+transition · 2013-07-10 09:54 · Score: 1
  
  Not all ion clocks are optical. Linear ion trap microwave clocks based on Yb and Hg were developed in the 90s. Some Hg clocks operated as part of the NASA Deep Space Network for a number of years and there's currently an active project to develop a highly miniaturised Yb clock. So the summary should say that lattice clocks can beat single ion clocks on QPN and fountains because optical beats microwave.
A good time to be a time nut by bryanandaimee · 2013-07-09 10:25 · Score: 1

Between this and the WWVB anniversary it's been a good run the last few days for time nuts.
"A man with one clock knows what time it is. A man with two clocks is never sure. But I would add further: A man with three clocks is more sure than a man with two clocks."
Quoted from one of the quintisential time nuts at
http://www.leapsecond.com/
Meh by multimediavt · 2013-07-09 10:40 · Score: 1

It's all relative.
Cesium Fountain Clocks? by DigitAl56K · 2013-07-09 10:52 · Score: 2

.. now that's what I call sloppy seconds.
So what happens to ... by hymie! · 2013-07-09 11:56 · Score: 4, Funny

So what happens to the platinum second they keep in the French vault?
1. Re:So what happens to ... by Nivag064 · 2013-07-09 17:19 · Score: 1
  
  No problems.
  They will still keep the platinum second - but it won't need as much cleaning, as it will not have to be brought out so often for calibration purposes...
Time Crystal by Bengie · 2013-07-09 13:38 · Score: 1

What about the 4 dimensional "time crystal" that not only has perfectly repeating latices structure in the 3 dimensions, but also in the 4th time dimension. If it truly has perfect repetition in the 4th dimension, shouldn't that be the "perfect" time piece?
1. Re:Time Crystal by Nimey · 2013-07-09 15:18 · Score: 1
  
  You mean the Time Cube?
  
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2. Re:Time Crystal by Brett+Buck · 2013-07-09 17:22 · Score: 1
  
  I hear that has 4 simultaneous days in one single rotation of the Earth and that anything else is evil oneness. Gotta get me some of that
Re:Who modded this up? by godefroi · 2013-07-10 05:30 · Score: 1

Including his sig...

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