A paradox on special theory of relativity

Discussion in 'Physics & Math' started by ash64449, Apr 14, 2013.

  1. ash64449 Registered Senior Member

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    795
    no need to reply to any of the post. The answer to this thread is that the paradox dosen't make any sense. Because "moving" is relative. If train is moving relative to one observer,it can also be rest relative to some other observer. So we cannot say that train is "moving". This paradox which dosen't make sense came because i thought an absolute frame of reference which it not there. Like pk said,i included something that is contradictory to relativity at first itself. I thank pk for making me realise this.
    I exactly don't know whether pk actually meant this or not!!
     
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  3. Prof.Layman totally internally reflected Registered Senior Member

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    Easy, they both arrive at the same time according to the MME in both frames, so then there is no such paradox. Then each frame just observes the flashes to arrive at the same time while their clocks then read different times. Things happen at the same time even though their clocks do not read the same time.
     
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  5. ash64449 Registered Senior Member

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    795
    sorry layman.not like that..my experiment says that observer in the middle should see those two events non-simultaneous.think how light should reach him if he should see them non-simultaneous??
    This paradox is solved..
     
    Last edited: Apr 15, 2013
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  7. Prof.Layman totally internally reflected Registered Senior Member

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    Why would I delude myself into thinking that they will not reach the same location at the same time when the actual experiments say that they do? They just don't reach the same location at the same time when their clocks would say the same thing.

    It is just confusion from interpretations of the Einstein TE. If you take the TE out of the equation there is no paradox. They arrive at the same time when their clocks would then read different things. The clocks just don't agree with each other when this happens.

    They just wouldn't arrive at the same time if spacetime was Newtonian, and then in order for events to be seen as happening at the same time would then require their clocks to read the same time at that event. But, clocks tick slower and faster than each other, with all the things in the Universe going on things have to happen at the same time regardless if their clocks say the same thing or not. Clocks can read different times and then have events be simultaneous even though the event doesn't happen when the clocks say the same thing.
     
  8. ash64449 Registered Senior Member

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    Still you think Einstein's thought experiment is wrong?
     
  9. eram Sciengineer Valued Senior Member

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    1,877
    ash, Prof. Layman doesn't know his stuff, don't let him mislead you.
     
  10. ash64449 Registered Senior Member

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    795
    yes.you are right..
     
  11. LaurieAG Registered Senior Member

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    Ash 64449 look at the paradox in a slightly different way.

    In the attached image the two digital counters would show the same count regardless of how fast the glass plate was spinning. Each count is created by connecting an electric current between A and B that increments the equidistant counters, the wires run under the glass plate and each wire is permanently connected to the central spindle by frictionless brushes, or whatever, on different sides of the plate. How can the two timers display different times?
     
  12. RJBeery Natural Philosopher Valued Senior Member

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    Ash, there is a mechanism (presumably on the train) which determines whether or not both switches are on at the same time. The observer on the ground will claim that the mechanism is inaccurate. This can be rectified by making the mechanism work with the concept of simultaneity relative to the ground...but then the train passengers will claim that the mechanism is inaccurate.
     
  13. Tach Banned Banned

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    5,265
    this is false, as i already explained in post 2. there is a mechanism that allows all observers to agree on simultaneity. the physical setup and the math are both trivial.
     
  14. Janus58 Valued Senior Member

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    Yes it does. The electrons traveling in the wire are subject to Relativistic velocity addition.

    Assuming that the electrons move at u relative to the train as measured by the train and that the train has a velocity v with respect to the embankment:

    Then electrons going in the same direction as the train are traveling at

    \(\frac{u+v}{1+\frac{uv}{c^2}}\) With respect to the embankment.

    And electron going the the opposite direction are traveling at.

    \(\frac{u-v}{1-\frac{uv}{c^2}}\) with respect to the embankment.

    as measured by the embankment observer.

    If you take the difference between these velocities and the speed of the train you get the result that according the embankment, electrons going in one direction move at a different speed with respect to the train than electrons moving in the other. The difference is such that you will get exactly the same end result if you use electrical signals as you do using light traveling in a vacuum.
     
  15. Russ_Watters Not a Trump supporter... Valued Senior Member

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    When I was in high school, I was arrogant about my intelligence too. I remember challenging my calculus teacher about an issue that I can no longer specifically recall. But I do remember that I was wrong and I realized shortly after that arguing with my teacher was getting in the way of learning, so I changed my attitude.

    So yeah, there is ample time for you to avoid becoming a crackpot. It requires an attitude change based on the recognition that you are not, in fact, The Smartest Person Who Ever Lived. And in the meantime you're being really, really annoying.
     
  16. eram Sciengineer Valued Senior Member

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    1,877
    I think most crackpots start when they are fairly old, when they have more free time.

    In his case it's less to do with crackpottery and more to do with his poor language abilities.
     
  17. ash64449 Registered Senior Member

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    I agree i have poor language abilities.But you don't have to keep saying again and again...
     
  18. ash64449 Registered Senior Member

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    Well,i am not doing like what you did when you were my age. I was really asking my doubt.But my language is bad.So when you guys read my comments,you guys thought i was telling that Einstein was wrong.No,i am not.But it sounded like that.Just like eram said,i have problem with language.In other words, i am not able to express what i am actually want to say...
     
  19. ash64449 Registered Senior Member

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    795
    And i am not a crackpot....
     
  20. ash64449 Registered Senior Member

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    Well,Thanks for the advice!!
     
  21. eram Sciengineer Valued Senior Member

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    Hey, I'm helping to explain it to others.

    No offence, if you asked me to write Hindi I would flop too.

    Please Register or Log in to view the hidden image!




    And please stop posting so many times in a row.
     
  22. ash64449 Registered Senior Member

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    Yes.You are right... It is kind of disturbing when i post 3 times for a single post...
     
  23. eram Sciengineer Valued Senior Member

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    1,877
    finally, you realize it.
     

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