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Using time dilation to determine absolute speed?

  1. Sep 1, 2015 #1


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    So if time dilation is what's left after correcting for the optical effect and we want to know our motion through the universe. We can't use light because we have no reference point to what not being in motion is and there's lots of attempts using light which doesn't work.
    Why don't we just take a few atoms we know the decay rate of and send them in different directions. As motion makes them last longer the one's travelling in a direction that reduces there overall motion should last the least amount of time and the one that lasts the least amount of time would not be in motion. Then deducting that motion from our own will give us a reference to what no motion throughout the universe is. Then everything would be a lot more relative =)

    Would that work ?
    Last edited by a moderator: Sep 1, 2015
  2. jcsd
  3. Sep 1, 2015 #2
    It would not work: the relativity postulate also works for radioactive decay. For uniform motion we cannot establish a "preferred frame", instead any uniform straight motion reference system is equally suitable for the laws of physics. But to understand how that can be possible, it is necessary to understand "relativity of simultaneity".
  4. Sep 1, 2015 #3


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    Staff: Mentor

    Although we send them in different directions, they will show the same amount of time dilation relative to us. Furthermore, if someone moving relative to us tries this experiment, they will get the exact same results as well.
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