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Logical Errors

  1. Jul 5, 2003 #1


    Experiments can't prove something which is logically flawed. Einstein's invalid procedure in deriving his transformation equations besides (see http://www.physicsmyths.org.uk/lightspeed.htm), motion is always only relative, so each of two obervers moving relatively to each other can claim that he is resting and the other moving, which makes it ambiguous which of the two clocks is going slower. In transverse Doppler effect experiments with source and receiver moving uniformly relatively to each other, an observer moving with the source would have to claim that the receiver has a lower than the rest frequency due to the motion, so he would have to lower the frequency of the emitter for the signal to match the receiver frequency. On the other hand, an observer moving with the receiver would claim that the emitter has a lower frequency due to the motion, so he would have to lower the receiver frequency in order to be able to receive the signal. This is obviously a logical contradiction because if both the emitter and receiver frequency are lowered by the same amount, it might as well remain unchanged. Yet in corresponding experiments the frequencies are not the same but detuned by a corresponding amount. This shows that the notion of moving clocks running slower is wrong. The observed 'transverse Doppler effect' either has to be a physical effect due to forces acting on emitter or receiver, or is in fact the normal Doppler effect associated with small distance changes between source and receiver which have not been taken into account for the experiment.
     
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  3. Jul 5, 2003 #2

    Hurkyl

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    You are correct that it is ambiguous, but you are incorrect as to the cause of the ambiguity. It is ambiguous because you have not specified in which reference frame you are comparing the rates of the two clocks.



    I don't see how any part of your exposition follows logically...

    The frequency of the source as observed in the reference frame of the source will be higher than the frequency of the source as observed in the reference frame of the receiver. Corrections are made to allow reception as necessary, either by dialing up the source or dialing down the receiver.

    (I'm presuming the source and receiver are moving away from each other, possibly at an angle)
     
  4. Jul 5, 2003 #3

    Integral

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    The only logical error demonstrated here is in the linked web page.

    The quanities t= L/(c-v) and t = L/(c+v) are indeed used by AE in his paper, but they are used as I have expressed them as an expression as the TIME required to travel the distance L. L is the length of a rod moving with the velocity v. The above expressions are the times as measured by an observer watching the rod move past as the light beam travels first in the direction of motion of the rod then its return trip.

    If you wish to argue errors in AE's math you will first need to read and understand the development he presents. Clearly this author has not done that.
     
  5. Jul 5, 2003 #4
    Einstein didn't derive the transformation equations, Lorentz did, that's why they're called the Lorentz Transformation.

    I was just thinking today that Einstein's paper is nearly 100 years old but there are still people who don't quite get it.

    And there's nothing logically flawed with the Theory of Special Relativity, it is a seamless whole. There isn't a place in it you could wedge a knife blade into.
     
  6. Jul 5, 2003 #5

    Integral

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    Lorentz's did not DERIVE the equations they were emperical, sort of a "hey look this works" set of equations with no real physical basis. Einstein showed that they could be mathematically derivived with only 2 assumptions. 1. That the laws of physics hold in all inerial frames. 2. That the speed of light is a constant to all observers. This is why AE gets credit for developing relativity and we still refer to the Lorentz transforms.
     
  7. Jul 5, 2003 #6
    Here are two links that describe the Lorentz Transformations, and both say that H.A. Lorentz first found them.

    http://www.wikipedia.org/wiki/Lorentz_transformation

    http://www.adi.uam.es/Docs/Knowledge/Fundamental_Theory/rltvt/node3.html
     
  8. Jul 5, 2003 #7

    Integral

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    Tyger,
    Did you read my post? There is no doubt that Lorentz first wrote down the Lorentz Transforms, that is why they are named that. Do you you understand the difference between derived and empirical? An empirical relationship does not have to have any physical basis, such as the relationship Balmer arrived at to describe the Balmer series in the Hydrogen spectrum. With knowledge of a constant c from Maxwell, Lorentz arrived at his transforms because they worked, Einstein showed the physical basis for them.
     
  9. Jul 6, 2003 #8

    Tom Mattson

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    Integral,

    I think it would be helpful if you post links to the details you worked out for On the Electrodynamics of Moving Bodies.
     
  10. Jul 6, 2003 #9

    Integral

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    Consider it done

    AE let some minor steps to the reader, here I have filled in the holes. The math needed is trivial, the concepts are a little deeper.
     
  11. Jul 6, 2003 #10

    drag

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    Greetings !
    Remarkable !
    I think people MUST frame this quote and put it on the
    door step of every University so that people could walk
    all over it as they enter. (No offense Thomas, I'm
    just talking about this sentence.)

    Live long and prosper.
     
  12. Jul 6, 2003 #11

    selfAdjoint

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    Here is a link to Weisstein' Desciption of Lorentz's EM work. It sure doesn't sound very empirical to me!
     
  13. Jul 6, 2003 #12
    Lorentz beleived his first equation

    was involved with "ether contraction" so it didn't seem merely empirical to him, it had a physical basis. And yes, there's no doubt that Einstein put the whole picture together with a minimum of principles and discarded the Ether in the process.
     
  14. Jul 9, 2003 #13
    This thread was hijacked

    Just for information:
    this thread has been hijacked from the thread 'time dilation' (https://www.physicsforums.com/showthread.php?s=&threadid=3498). What's more, my account (Thomas) has been disabled without any notice and explanation and I am therefore not even able to comment on it anymore.
    Whoever did this should ask himself some serious questions regards the legality of his actions. Not only are they extremely offensive but could even be considered as libellous, as, contrary to the appearance, I did not start any thread called 'Logical Errors'. It was started by somebody who stole one of my posts and pretended to be me.
     
    Last edited: Jul 9, 2003
  15. Jul 9, 2003 #14

    Janus

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    Re: This thread was hijacked

    Your posts were merely split off to start a new thread by the mentor as he felt that they were de-railing the original thread.

    Also, since your posts were moved intact, and with no changes, your charges of libel are laughable.

    Besides, when you registered, you agreed to the forum rules when you clicked the "I agree" button. These rules state :
    "The owners of Physics Forums have the right to remove, edit, move or close any thread for any reason."
     
  16. Jul 9, 2003 #15
    Re: Re: This thread was hijacked

    I am afraid your assertions don't make any sense in the light of the fact that my account was suspended without any warning.
    Also, only the one post and not the whole thread was moved, and my post was therefore taken out of context.
    Anyway, I can't see how it can be seen as a derailing of a thread when I was explicitly responding to a previous post (Ahrkron's).
     
    Last edited: Jul 9, 2003
  17. Jul 9, 2003 #16

    Integral

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    Opps, you are right Thomas, I did make a mistake. I left this split off thread in Physics, I should have moved it to Theory Developement. My first inclination was simply to delete it. But since your reply to Ahkron was so blatently off the topic of the thread I decided to play with the thread split feature.

    Gregg, the thread split works great!

    Thomas, to be a valued member of this forum you need to make an effort to reply to the topic at hand. Please avoid converting threads to your personal agenda.
     
  18. Jul 10, 2003 #17

    russ_watters

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    QM comes to mind. Most of the major points of QM are logically flawed but they are about as thoroughly proven as any scientific theory can be.

    A photon (electron!) in two places at once? Preposterous.

    P.S. guys, the debate on whether the Lorenz Transforms were derived or discovered is kinda pointless and petty. It doesn't make a whole lot of difference. You guys are agreeing on far more than you are disagreeing.
     
    Last edited: Jul 10, 2003
  19. Jul 10, 2003 #18

    drag

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    You should read what I said about that sentence...:wink:
     
  20. Jul 10, 2003 #19

    russ_watters

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    I think I did. You mean the one about college doormats? Great post and I was thinking of quoting it. But I was agreeing with you. So... [?] [?]

    Btw, I've already copyrighted that sentence and the doormats should be on sale at WallMart within a few weeks.
     
  21. Jul 10, 2003 #20
    Blatently off the topic ?? The original topic was about time dilation experiments and that's what the moved post (the first post in this thread) addresses. It was you and others who subsequently derailed this thread by turning it into a discussion about the history of the Lorentz Transformation.
     
    Last edited: Jul 10, 2003
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