Can the Twin Paradox be simplified?

Discussion in 'Physics & Math' started by timewarp, Nov 20, 2011.

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  1. Tach Banned Banned

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    Go to 139
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  3. RJBeery Natural Philosopher Valued Senior Member

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    Please stop changing the subject. Your proper times analysis was done from a different starting point than mine. You started at the Unprime/Tripleprime passing event while mine started at each brother's watch reading of 0:00, as I explained. I understand why you're tap dancing like this but it will not get you out of this pickle:

    [Extensive analysis given]
    That's six times you've literally ignored the question, as if you never even read it. Why might that be?
     
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  5. Tach Banned Banned

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    I am not changing the subject, I am consistently pointing out that you don't understand the meaning of proper time and that you messed up its calculation resulting into your claim that you contradicted basic mainstream relativity:


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    Last edited: Dec 7, 2011
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  7. RJBeery Natural Philosopher Valued Senior Member

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    Tach, you can play that game all you want, your maturity level has already been established. I'd like to point out that (if we include the repeated inquiries in my previous two posts, as well as the following one) we're now up to nineteen requests for a response:

    Are you going to claim that, with proper calculations, the conclusions drawn by Unprime and Doubleprime will be in agreement with those drawn by Prime and Tripleprime? If so, what conclusions would those be, specifically?
     
  8. Tach Banned Banned

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    I did, your oft- repeated question makes no sense, asking it repeatedly shows that you don't understand the meaning of proper time being an invariant and that you messed up all your attempts in determining proper time, hence concluding that you have "disproved" mainstream physics. See post 139.


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    Last edited: Dec 7, 2011
  9. RJBeery Natural Philosopher Valued Senior Member

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    You're manufacturing excuses. The question stands on its own and makes no mention of proper time.

    #20: Are you going to claim that, with proper calculations, the conclusions drawn by Unprime and Doubleprime will be in agreement with those drawn by Prime and Tripleprime? If so, what conclusions would those be, specifically?
     
  10. Tach Banned Banned

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    No, the question is nonsensical and you generated it through mistakenly calculating different values for the proper time of the same twin and further claiming that you have refuted mainstream physics. This is a gross mistake that contradicts mainstream physics since proper time is known to be frame invariant thus terminating this thread.

    Go to post 139

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    Last edited: Dec 8, 2011
  11. RJBeery Natural Philosopher Valued Senior Member

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    I understand the invariance of proper time just fine. I calculate different times when we change the delimiting endpoint events. I can't believe I have to hold your hand through this when others such as Janus walked himself through it and figured it out in a single post...

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    Anyway, here it is from UNPRIME'S perspective: Unprime and Prime say goodbye when their clocks read 0.00. At .75 on Prime's watch, Prime passes Doubleprime and they sync up. Then, at 1.5 on Doubleprime's watch, he meets Unprime. Unprime knew that the relative speeds (and therefore the clock rates) of Prime and Doubleprime are equal, so he declares that Prime's watch "now" says 1.5 while his reads 2.5, therefore UNPRIME DECLARES THAT PRIME IS YOUNGER.

    From PRIME'S perspective: Prime and Unprime say goodbye when their clocks read 0.00. At 1.25 on Prime's watch, Tripleprime passes him and they sync up. Then at 2.5 on Tripleprime's watch, he meets Prime. Prime knew that the relative speeds (and therefore the clock rates) of Unprime and Tripleprime are equal, so he declares that Unprime's watch "now" reads 2.5 while his reads 4.166, therefore PRIME DECLARES THAT UNPRIME IS YOUNGER.

    You see, it isn't just about proper times. The fact that proper times are invariant is IRRELEVANT when you must also take into consideration their RELATIVE LINES OF SIMULTANEITY if you're going to determine which segments of their worldlines you are measuring.

    Get it now?
     
  12. Tach Banned Banned

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    No, you don't. Until yesterday you didn't even know what proper time was. Anyways, you calculated different values for the proper times of the same twin, a rookie mistake that lead you to contradicting statements that contradict mainstream physics:

    ....and the comedy continues

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    Oh, one more thing, the values you calculated for proper times have been already proven wrong in whatever frame you did your calculations.
     
  13. RJBeery Natural Philosopher Valued Senior Member

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    Tach, if I thought it wasn't obvious to others reading this thread that I do and always did understand proper time, I would make efforts to correct you. I'm not taking the bait in your attempt to change the subject.

    Anyway, which of the following statements is comedic to you:

    1) From Prime's perspective, Prime declares that Unprime is younger.
    2) From Unprime's perspective, Unprime declares that Prime is younger.
     
  14. Tach Banned Banned

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    I can see that you are still struggling to understand the meaning of proper time.
    It will be a long time before you come to grips that it (proper time) is an invariant, so changing frames of reference doesn't change its value.
    I predict that it will be even longer before you manage to calculate the values for the proper times for the twins correctly.
     
  15. RJBeery Natural Philosopher Valued Senior Member

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    Your refusal to answer the question speaks volumes.
     
  16. Tach Banned Banned

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    Your keeping formulating these kinds of questions demonstrates that you have no understanding of the notions being manipulated. Let's try something a lot simpler: Prime and Tripleprime raced each other to a common point in space at speeds of 0.8c and 0.9756c respectively, both measured with respect to Uprime's frame. At the end of the race they compared their watches.
    Which one has less elapsed time? For extra points: if one changes the frame of reference does the result change? (Hint: it doesn't).
     
    Last edited: Dec 8, 2011
  17. Janus58 Valued Senior Member

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    Okay, here are four space-time diagrams for the frames of reference. I was forced to make a couple of changes. Prime's velocity with respect to Unprime is 0.25c and Tripleprime's velocity to Unprime is 0.5c.

    Keeping the original values made the diagrams too unwieldy in some the frames. For example, this pair of S-T diagrams are of the same world-line segments using the original relative velocites, drawn from two different frames. Dark blue is Unprime, Green is Prime, Red is Double prime and Light blue is Tripleprime. Even though I don't even extend Prime and triple prime out to when they meet, switching to the frame of Doubleprime, stretches out the diagram a great deal.

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    So keeping the same color convention for world-lines as above, here's the diagrams for all four frames.

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    I chose a scale so that Unprime reads 200 upon meeting up with Doubleprime. I assumed that each clock's 0 time just happened to be such that Unprime and Tripleprime have the same clock reading when they meet as do Prime and Doubleprime, and Prime and Unprime read zero when they meet.

    First off, I fail to see what adding the forth frame (Tripleprime) does in clarifying anything. If you want to show that simultaneity of clock readings are different between frames, that is readily apparent from just the original three frames.

    Secondly, I fail to see any "contradictions". I only see what is to be expected in a Relativistic Universe.
     
  18. RJBeery Natural Philosopher Valued Senior Member

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    LOL! Tach the fact that you ask this question exposes the reason why you're so confused. A proper time needs a definitive beginning point and end point on a world line. Your end points have been chosen by the twins meeting, and the beginning points have been selected by your CHOICE of Unprime's frame. Perhaps now you can understand why this isn't an issue of proper time's invariance but rather one of variant lines of simultaneity. If we re-ran the race from a frame other than Unprime's, we would either claim that one of the twins started early, started late, or had his watch not properly set when we said "GO!". Therefore the result DOES CHANGE IF WE CHANGE FRAMES!

    You see, your ranting about proper times being invariant is a red herring. I'm trying to decide if you knew this the whole time and are intentionally being a troll, or if Arfa Brane, OnlyMe and Janus are simply that much more intelligent than you.
     
  19. RJBeery Natural Philosopher Valued Senior Member

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    Janus, I have to apologize but I have to leave so I cannot give your post the attention it deserves until later. However, this comment is basically my entire point! If the fourth twin gives us no new information, what new information did the third twin give us? The third twin certainly did not establish any undeniable time dilation for any participant, so how is it any different than TWO twins simply passing each other in the dead of space and making the conflicting observation that each seems to be moving more slowly than the other?

    My point is that there are people (such as Tach) who assume the Third Twin establishes something that it doesn't. Let me ask you a question, and I would appreciate an intellectually honest answer: when you when you first walked yourself through my thought experiment were you not surprised in the least about the conclusion?
     
  20. Tach Banned Banned

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    How many times do I need to explain to you that the results are the same in all frames. Proper time is an invariant, so one can choose any frame to work with. This is also why your results are wrong in any frame.


    See, you still don't understand your own little exercise. Don't worry, one day, in the distant future you might get it.



    Janus58 says you are wrong.
    Arfa and OnlyMe have contributed nothing.
    You have "contributed" a long list of hilarious mistakes.
     
  21. RJBeery Natural Philosopher Valued Senior Member

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    You know, Tach, if my grandmother had wheels she'd be a trolleybus!

    Your start points change when you change frames in your scenario. In my original graph, it's the end points that change when we change frames. Proper times are invariant only when the start and end points do not change. You're appearing like a child screaming "LALALALALA" with your fingers in your ears on this.

    I would be quite surprised if Janus says I'm wrong on this issue.
     
  22. Neddy Bate Valued Senior Member

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    I had always thought the idea of the third twin was to establish that time dilation was not caused by acceleration. The third twin gives us the same result as if one of the twins had accelerated, but since none of the twins had to accelerate to provide this answer, it proves that acceleration is not the cause.

    But apparently RJBeery had a different interpretation of what the third twin's purpose was. He thought the third twin was supposed to establish which of the first two twins was actually younger than the other. So his thought experiment was designed to demonstrate that no matter how many twins you use, you still don't get a definitive answer as to which of the first two twins was actually younger than the other.
     
  23. Tach Banned Banned

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    Reality check
     
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