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Latest atomic clock smashes records with 15 billion year accuracy

By Scorpus ยท 42 replies
Apr 22, 2015
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  1. latest atomic clock clock record breaker strontium

    Atomic clocks are some of the most important measuring devices on Earth, as they are used for master clocks that essentially dictate the time standard used pretty much everywhere. See the time on your computer or smartphone? That has almost certainly been synchronized with an atomic clock in the past day or so.

    While atomic clocks are already unbelievably accurate, a new atomic clock has been developed by JILA researchers that has set a world record for accuracy and stability. This new clock is a factor of three more accurate than the previous world record holder, meaning that it won't lose or gain more than a second after 15 billion years of operation.

    In other words, this clock could continue to "tick" for longer than the current age of the universe, and it would barely lose any time at all.

    The way this atomic clock works is rather complicated. Inside the clock mechanism, an optical lattice is formed by strong lasers, which hold a bunch of strontium atoms in place. A red laser then forces these atoms to switch between different energy levels, and each switch corresponds to the tick of a clock.

    This new record-breaking atomic clock managed to improve upon accuracy and stability by using a new and much more stable laser, more precise control over the clock's temperature, and improved measurement techniques. The clock is now so sensitive that it's affected by changes in gravity: moving the clock up in height by just 2cm would affect its output.

    The researchers hope that this clock can not just be used to keep ultra-accurate time, but also to conduct further research into quantum behavior and gravity variations.

    Permalink to story.

  2. stewi0001

    stewi0001 TS Evangelist Posts: 2,138   +1,555

    I wonder how much power this clock needs to stay operational.
  3. I'll come back in 15 billion years and see if it's still accurate. ;)
  4. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    And maintaining altitude over 15 billion years is not only theoretically impossible but completely impossible. Which makes this claim completely false. I doubt the same altitude can be maintained over 1000 years much less 15 billion.
  5. Skidmarksdeluxe

    Skidmarksdeluxe TS Evangelist Posts: 8,647   +3,286

    How do you wind it up? :D
  6. Igrecman

    Igrecman TS Maniac Posts: 257   +156

    That's stupid, since the earth's rotation is slowing down 0.005 seconds per year. This rate of 0.005 seconds per year would result, in 5 billion years, into days of almost 40 hours. If they have to input this correction in the programming of the clock, what's the difference of inputting a greater correction in a less accurate clock? LOL
  7. Changes in the speed of the planet's rotation has nothing to do with the measurement of time. A day-night cycle, such as Earth's 24hr day, is a measure of a given quantity of time that exists between two points. If the planet slows to a 40hr day, it isn't the clock that needs to be corrected, it's the calendar.
    SirChocula likes this.
  8. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    ^^ I'm not even gonna bother commenting to the inaccuracy of that statement.
  9. Scorpus

    Scorpus TechSpot Staff Topic Starter Posts: 1,971   +231

    The claims definitely refer to the theoretical situation where you would keep the gravitational field the clock is under constant

    You're referring to civil time, which is different to atomic time. Atomic time stays constant, while civil time has leap seconds and all that stuff added so that it approximates the day/night cycle of the Earth
    davislane1 likes this.
  10. The claim is not false. Have you heard of relativity? The clock will remain accurate to any observer within the same relative space. This is how clocks can actually be used to measure the temporal effects of gravity, which are very real and already observed in GPS, which is also essentially just a system of clocks at its heart.
    Darth Shiv and Scorpus like this.
  11. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    OMG - here we go with Syfy that can't be proven, because common sense is overlooked. The clock is a measure of accuracy for everyone around the globe. Relative space has nothing to do with the planets speed of rotation or planetary orbit around the sun. Neither does it have anything to do with continental drift that would eventually alter synchronization, as the continents change shape.
  12. 1. Time remains constant, all else being equal.
    2. An Earth day is defined as the quantity of time required for the planet to rotate 360 degrees.
    3. A rotation of 360 degrees can only occur if an object moves around an axis from point A to point B.
    4. Therefore, if the rotational speed of the planet slows, the quantity of time required to move from A to B increases and days become longer.

    What is inaccurate about this?
  13. Again, time is not a measure of rotation of the Earth itself. Same as a meter is defined as a certain amount of time light takes to travel. If the Earth slows then what has to change is the clock we make to define a day.

    On a lighter note, I wonder if intricate adjustments have to be made to account for mass that the Earth fain from space debris seeing how accurate the clock is.
  14. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    No time is not, but the measure of time as we measure it is.
  15. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    The fact that a day is divided by a 24hr clock and over the centuries this will likely not change. With the gradual change in the length of one day, the length of one second will remain proportional, unless we change from using a 24hr clock. As for the calendar there are other factors to include not just the rotation speed of a planet. You made an assumption the calendar would need to change based on one variable.
  16. wiyosaya

    wiyosaya TS Evangelist Posts: 3,710   +2,074

    Maybe I am not getting exactly what you are stating here, but if the length of the day changes, then assuming that at the time when the length of the day is 40 hours, then there will be approximately 144,000 seconds in a day instead of the current approximate number of seconds 86,400.

    The length of the second will not change unless we once again change the definition of it. A "second" is currently defined as

    which, in all relativistic time frames, will be the same (assuming Einstein is not disproved at some time in the future).

    See the wikipedia entry - it is quite accurate in its description of the definition of the second.
  17. Tye Lucas

    Tye Lucas TS Rookie Posts: 18

    He's right, time is time, which is not measured by the amount of hours in a day on earth...quite the opposite...
  18. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    24 hours stretched out to be 40 of our current hours. If the time of day doesn't stay at 24 hours, we will need to use a different clock. Can you imagine saying their is 25 hours in a day? When exactly would the switch be? Or would we gradually take it to 25 hours making 24 hours and 21 minutes somewhere in between? No the clock will remain a 24 hour clock or we will stop using it.
    The measure of time we use as our clock is based on the length of time in one day. It is broken down into 24 hours. And if one day lengthens so will the hours, minutes, and seconds within. One second will not remain constant if the planet changes rotation speed without breaking our clock increments.
    Last edited: Apr 22, 2015
  19. The current official definition of a second:
    The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.

    What does that have anything to do with an earth day. And, how can they prove 15 billion year accuracy, what if a cosmic ray hits it tomorrow.
  20. If, billions of years from now, the planet's rotation slows sufficiently to add 2hrs in total time to a full rotation, traditional clock increments are broken. An hour is still an hour, a minute is still a minute, and a second is still a second. What changes is the total number of units on a clock face. A 13th hour would need to be added to a traditional clock face.

    You are conflating calendar days with units of time. The two are not the same.

    The only potentially misleading this about this conclusion is that the "clock" doesn't need to be corrected. If a day increases significantly in time, more units need to be added to a traditional clock face to account for the change. But an atomic clock or similar device needn't be adjusted in such a manner, because it tracks time, not calendar days. It is the calendar that needs to be adjusted to reflect the change in rotational speed, as lengthened day-night cycles results in shorter calendar years.
  21. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    Apparently you can't fathom the concept of 86,400 second in one day setting the period of time for that value. And if the period of time in one day changes (Our clock which dictates 86,400 seconds as a constant), so must that value. And if that value changes so must the atomic clock variables.
    You are not thinking this through completely, one hour is a huge jump. The changes will be gradual, not over night. You would have to add milliseconds(I didn't do the math) to the clock each century not hours.
    Last edited: Apr 22, 2015
  22. wiyosaya

    wiyosaya TS Evangelist Posts: 3,710   +2,074

    This is what I thought you were implying.

    Again, unless we change the definition of the second again, the second will remain constant. Please see the link I posted that states the definition of the second.

    While the second was previously defined in terms of the rotational speed of the Earth, the second is no longer defined that way, but rather by invariant atomic transitions under precisely controlled conditions. Atomic transitions, I.e., the levels an electron can take in their orbit around the nucleus of an atom, are what atomic clocks are based on and what make those clocks so accurate. Given the level of accuracy achieved by atomic clocks, I cannot see the definition of the second changing back to using the rotational speed of the Earth as a basis since that is, by its very nature, lacking in accuracy. If the definition changes, then I would hope that such a definition would be based on a more accurate atomic transition perhaps the transition of the strontium atom that this clock is based on.

    So, unless the definition of the second is once again changed, future Earthlings will have to add a sufficient number of seconds to the clock to accommodate the variance in the rotational speed of the earth - whether or not this is an unpalatable idea. This is precisely what is done right now for leap time.
    davislane1 likes this.
  23. Ergo, an atomic clock is more accurate than a traditional clock. Due to the decaying rate of Earth's rotational speed, the latter is increasingly inaccurate as a function of time.
  24. cliffordcooley

    cliffordcooley TS Guardian Fighter Posts: 11,208   +4,877

    And I'm trying to say that our clock is based on increment of one day. One second is a constant increment of one day. If the day gets longer so will the second. What is so hard to understand that one second in a length of time based on a specific increment of the day, not a specific length of time. The increment of the day is what dictates the length of time designated to the measurement of time.

    The constant you keep referring to is not a true constant, if the rotation of the earth can get faster or slower.
  25. The fact that this argument is provably wrong. (see previously cited material)

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