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Relative Direction

  1. Apr 24, 2004 #1
    This question may seem irrelevant, but I am asking nonetheless. I have only recently been introduced to Einstein's Relativity Theory. It really fascinates me. I read in one experiment conducted that two highly accurate clocks were synchronized and while one stayed stationary, the other was flown around the world from East to West at high speeds. Upon reuniting the two clocks, the times varied slightly. The clock that was in motion had less time showing, therefore proving Einstein's theory to be correct. My question stems from this experiment. Would we see the same results if the plane were flying from West to East, against the rotation of the earth? I would really appreciate any information, links, websites, or suggestions...thanks!
    Last edited: Apr 25, 2004
  2. jcsd
  3. Apr 25, 2004 #2
    Yes, and the answer isn't really that complicated. The speed at which an object moves is what makes a different in relativity, not its velocity. Theoretically, they could have taken the clock and put it on the edge of a huge spinning plate (say the size of those metal manual merry go rounds in cheap parks) and if the speed was the same, they would have had the same results.

    Also, is your information real or theoretical? I don't think our technology is capable of showing such a difference.
  4. Apr 25, 2004 #3
    "In that 1905 paper, Einstein pointed out that because you could not detect whether or not you were moving through the ether, the whole notion of an ether was redundant. Instead, Einstein started from the postulate that the laws of science should appear the same to all freely moving observers. In particular, observers should all measure the same speed for light, no matter how they were moving.

    This required abandoning the idea that there is a universal quantity called time that all clocks measure. Instead, everyone would have his own personal time. The clocks of two people would agree if they were at rest with respect to each other but not if they were moving. This has been confirmed by a number of experiments, including one in which an extremely accurate timepiece was flown around the world and then compared with one that had stayed in place. If you wanted to live longer, you could keep flying to the east so the speed of the plane added to the earth's rotation. However, the tiny fraction of a second you gained would be more than offset by eating airline meals."

    This is an excerpt from


    I see your point. Thanks.
  5. Apr 25, 2004 #4
    Although space and time or spacetime are now considered relative to some frames of reference in uniform motion with each other, the absoluteness or relativeness of the concept of 'direction" remains an open question to this day.

    Our intuition tells us that time is flowing but no one knows in what direction. Our theory tells us that the universe is expanding but no one knows where is the center of this expansion. These two examples beg the question for a clear definition of "direction" in math and physics. The flow of time and expansion of the universe are truly the invariant symmetric properties of nature. Whoever breaks this symmetry holds the key to a door that allows one to enter into the formulation of a theory of everything.
  6. Apr 25, 2004 #5
    Yes. Thank you. That was more along the lines of what I was trying to express. It's good to know that although there may be no answer, at least the question was relevant!
  7. Apr 25, 2004 #6
    No answer yet. But I am working on it, day and night. And I even quit my employment just to find time to do the research.
  8. Apr 25, 2004 #7
    Wow! Blessings to you. I agree, it is enough to keep the motivation flowing!
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