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If time was stopped, is inertia conserved?

  1. Dec 31, 2005 #1


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    Ok, if I stopped time, and started it again. Would all the inertia of everything be "forgotten?" Or "remembered?" Would bullets suddenly fall to the ground from mid-air? Do you understand me?
  2. jcsd
  3. Dec 31, 2005 #2


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    Gold Member

    As much as I hate to admit it, I do understand you. :tongue:
    Unfortunately, we can't stop time. If we could, I'd still be 25 years old. By relativity, all inertial frames have their own time. The only way to stop it is to travel at light speed. Since only massless particles can do that, there is no inertia to conserve. Time is more or less measured by the change of state of some system or other, so stopping it would by definition prevent any change at all from occurring. The closest that you can get is to take a picture of something. That's one instant of time frozen in place.
  4. Dec 31, 2005 #3
    If you think about it, when you 'see' something, it's all about light hitting your eyes. So if time stopped, light would no longer travel and you would (of course, this can't happen as time's stopped for you as well) see nothing. I'm probably horrible wrong, but oh well.
  5. Dec 31, 2005 #4


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    Staff: Mentor

    Inertia is resistance to acceleration and its units do not include time - so what does that have to do with bullets falling to the ground?
  6. Dec 31, 2005 #5


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    Yes, if time stopped, laws of physics would indeed be violated. But this sentence is devoid of any meaning. Time not stopping IS one of the laws of nature, so it's like asking "If the earth were flat, what would it be resting on?".
  7. Jan 1, 2006 #6
    Falling of bullets back to the ground from mid-air is again an order of events ... whihc is titled 'time' again! ... STopping time would simply limit increase/decrease the fourth coordinate of the proposed space-time structure.Gained inertia maybe from a force or a collision , because the result of inertia is another 'set of ordered events appropriately responding to the action as per the laws of physics' , all these ordered events can perform each step of the order ONLY when the fourth coordinate time moves forward . Thus stopping time would simply restrict motion , bringing the object to a standstill.

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