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  1. Standard member sonhouse
    Fast and Curious
    13 Nov '12 14:31
    http://phys.org/news/2012-11-surveying-earth-interior-atomic-clocks.html

    This goes way beyond what I used to work on at Goddard Space Flight Center, our atomic clocks back in the Apollo days was accurate to about 1 second in 2000 years, I think these clocks are more like 1 second in a billion years or so.

    Since time flow varies with mass, you can use an atomic clock to measure the geode of the Earth, if you are over a heavy mass, time slows down, over a lighter mass, the clock speeds up.
  2. 14 Nov '12 07:05
    Originally posted by sonhouse
    http://phys.org/news/2012-11-surveying-earth-interior-atomic-clocks.html

    This goes way beyond what I used to work on at Goddard Space Flight Center, our atomic clocks back in the Apollo days was accurate to about 1 second in 2000 years, I think these clocks are more like 1 second in a billion years or so.

    Since time flow varies with mass, you can use ...[text shortened]... Earth, if you are over a heavy mass, time slows down, over a lighter mass, the clock speeds up.
    Super cool:
    "In 2010 ultraprecise atomic clocks have measured the time difference between two clocks, one positioned 33 centimeters above the other,"

    And to think that at least one poster over in spirituality believes we have got it all wrong and that time is really absolute and our instruments are faulty or being misinterpreted.
  3. 14 Nov '12 10:20 / 1 edit
    Originally posted by twhitehead
    Super cool:
    "In 2010 ultraprecise atomic clocks have measured the time difference between two clocks, one positioned 33 centimeters above the other,"

    And to think that at least one poster over in spirituality believes we have got it all wrong and that time is really absolute and our instruments are faulty or being misinterpreted.
    oh yes, I know exactly what you mean. A few years back I argued against a religious fundamentalist ( don't remember his name ) that denied relativity and insisted that there is absolute time despite experiments with atomic clocks orbiting the Earth ticking slower than those on the surface of the Earth thus proving relativistic time dilation effects that prove relativity. His 'explanation' of the clock in space ticking at a slower rate was that the atomic clock “experiences stress” of being in space ( whatever that is supposed to mean -exactly what kind of “stress” would do that? Is there some special physics he knows about that we don't? If so, I wish he tell us what it is ).
    I wonder how these religious nuts that deny relativity explain how an atomic clock placed just a few centimeters above another always ticks at a slightly slower rate just as relativity predicts? I cannot imagine but you can bet on your life they will still deny it somehow. Perhaps they will lower themselves to resort to just saying all the observations are false and made-up and all this science is just part of a vast atheist conspiracy to disprove specifically their God? ( as if all these intelligent scientists want to waste their time doing that )
  4. 14 Nov '12 14:38
    Originally posted by twhitehead
    Super cool:
    "In 2010 ultraprecise atomic clocks have measured the time difference between two clocks, one positioned 33 centimeters above the other,"

    And to think that at least one poster over in spirituality believes we have got it all wrong and that time is really absolute and our instruments are faulty or being misinterpreted.
    Yeah, but it gives serious headaches for people trying to synchronise events/clocks around the world.

    Now they have to include precise data about exactly how far above the geode the clocks are.

    In fact it's worse than that, because the world is rotating you have to account for varying amounts
    of time dilation due to special relativity as well as general relativity.


    Keeping the worlds atomic clocks is a tricky business.
  5. Standard member sonhouse
    Fast and Curious
    14 Nov '12 15:08
    Originally posted by googlefudge
    Yeah, but it gives serious headaches for people trying to synchronise events/clocks around the world.

    Now they have to include precise data about exactly how far above the geode the clocks are.

    In fact it's worse than that, because the world is rotating you have to account for varying amounts
    of time dilation due to special relativity as well as general relativity.


    Keeping the worlds atomic clocks is a tricky business.
    Tell me about it! When I was with NASA on Apollo, we were taxed to get the clocks synced to within 100 nanoseconds, all of them around the world. I imagine now they do it within picoseconds.
  6. 14 Nov '12 17:40
    Originally posted by sonhouse
    http://phys.org/news/2012-11-surveying-earth-interior-atomic-clocks.html

    This goes way beyond what I used to work on at Goddard Space Flight Center, our atomic clocks back in the Apollo days was accurate to about 1 second in 2000 years, I think these clocks are more like 1 second in a billion years or so.

    Since time flow varies with mass, you can use ...[text shortened]... Earth, if you are over a heavy mass, time slows down, over a lighter mass, the clock speeds up.
    So we can expect that a fat man will start getting to work later and later.
  7. Standard member sonhouse
    Fast and Curious
    14 Nov '12 21:11
    Originally posted by joe beyser
    So we can expect that a fat man will start getting to work later and later.
    And those thousand pounder's should start living forever.....
  8. 14 Nov '12 21:31
    Originally posted by googlefudge
    Now they have to include precise data about exactly how far above the geode the clocks are.
    Not necessary. Synchronization and subsequent measurements will in fact tell you exactly how far above the geode the clocks are. It is not necessary to for the initial synchronization and because the drift due to geode will be constant, it can easily be corrected for over time. It is the variable effects that are a problem. I wonder if this effect can be used to precisely measure the rate that mountains/ continents are rising/sinking.
  9. Standard member sonhouse
    Fast and Curious
    14 Nov '12 21:44
    Originally posted by twhitehead
    Not necessary. Synchronization and subsequent measurements will in fact tell you exactly how far above the geode the clocks are. It is not necessary to for the initial synchronization and because the drift due to geode will be constant, it can easily be corrected for over time. It is the variable effects that are a problem. I wonder if this effect can be used to precisely measure the rate that mountains/ continents are rising/sinking.
    In effect they already are, super precise gps systems are directly measuring continental drift, which is for the atlantic plate, about 1 inch per year.
  10. 14 Nov '12 23:50
    Originally posted by twhitehead
    Not necessary. Synchronization and subsequent measurements will in fact tell you exactly how far above the geode the clocks are. It is not necessary to for the initial synchronization and because the drift due to geode will be constant, it can easily be corrected for over time. It is the variable effects that are a problem. I wonder if this effect can be used to precisely measure the rate that mountains/ continents are rising/sinking.
    Drift due to geode will only be constant if geode is constant.

    Mass of atmosphere/oceans/lunar gravity/tectonic movement all make the geode non-constant.
  11. Standard member sonhouse
    Fast and Curious
    15 Nov '12 03:18
    Originally posted by googlefudge
    Drift due to geode will only be constant if geode is constant.

    Mass of atmosphere/oceans/lunar gravity/tectonic movement all make the geode non-constant.
    But those things can be factored out by re-scans since they would be making many many measurements, going over land masses again and again. A geode won't move much, all those other things move, like the atmosphere changes daily and so does the moon.
  12. 15 Nov '12 06:47
    Originally posted by sonhouse
    In effect they already are, super precise gps systems are directly measuring continental drift, which is for the atlantic plate, about 1 inch per year.
    But gps although using clocks, does its work by measuring distance and time distortion is a factor that must be taken into consideration but removed from the equations. I am talking about measuring the time distortion and using that to measure position relative to the earth's gravity well.
  13. 15 Nov '12 06:48
    Originally posted by googlefudge
    Drift due to geode will only be constant if geode is constant.

    Mass of atmosphere/oceans/lunar gravity/tectonic movement all make the geode non-constant.
    Any idea how large these changes are? I believe the Japanese earthquake made a measurable difference to earth's spin, presumably by changing the geode.
  14. 15 Nov '12 08:49
    Is it possible that you can measure the depth of a gravity well by its effect on time more precisely than you can by more direct means?
  15. Standard member sonhouse
    Fast and Curious
    15 Nov '12 10:54
    Originally posted by iamatiger
    Is it possible that you can measure the depth of a gravity well by its effect on time more precisely than you can by more direct means?
    For buried geodes, the other method is the two satellite method where they have lasers measuring the distance between them and going over a geode changes that distance slightly, but the time clock way they mentioned the ability to see changes of 33 cm, 1/3 of a meter so it is probably more sensitive than the 2 satellite method and will get more sensitive as clocks get more accurate still.