Can the Twin Paradox be simplified?

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

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1. TrippyALEA IACTA ESTStaff Member

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That's the point, Tach.

If the accelerations cancel, but differences in elapsed proper time exist between the twins, then the only variable left that can have caused the differences in elapsed proper times for the twins is their relative velocity.

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3. TrippyALEA IACTA ESTStaff Member

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I think the funniest thing of all is that if I am a fool for proposing what I said, then so is the person that wrote that wiki entry you linked to, and so are you for linking to it.

:shrugs:

The only thing I'm proposing is a pretty minor variation to the restatement you yourself linked to.

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5. TachBannedBanned

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First off, thank you for being more civil this time and not hurling insults. Second off, the above is insufficient as a proof because anyone can content that the acceleration effects simply canceled each other , so you cannot conclude that acceleration played no role.

On the other hand, my approach conclusively proves that acceleration plays no role since there is no way that the acceleration effects canceled each other. This is a big difference and a standard procedure in setting up experiments, you cannot allow any suspicion that the effect that you want to test is zeroed out by the methodology. Your methodology zeroes out the acceleration effect right off the bat.

Asymmetry only STRENGTHENS the proof. The more the experiment is tilted in FAVOR of acceleration causing havok (and finding out that it doesn't) , the STRONGER the proof that it REALLY has no effect. The setup for your experiment is suspect, mine , by exacerbating the conditions, is not.

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7. TachBannedBanned

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This is precisely where your logic lacks, you are only proving that difference in velocity results into differences of elapsed proper time, the fact that you took away the acceleration you can not prove that acceleration plays no role.
By canceling the acceleration off the bat, you fail to prove that acceleration plays no role.
Do you understand your error in logic? Do you understand how your setup lacks?

8. TrippyALEA IACTA ESTStaff Member

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I will be as civil, or as rude to you, as you are to me, or anyone else in this thread.

The whole point of the experimental setup is that the twins are subjected to the same acceleration, and so the same effects due to acceleration.

No, it makes them equivalent. That's the point - the only difference between them is relative velocity.

No it isn't, because in my experiment both twins have been subjected to the same acceleration for the same amount of co-ordinate time, and have experienced the same effects because of it.

9. TrippyALEA IACTA ESTStaff Member

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You're being rude again, be careful, it's been demonstyrated repeatedly that the only lacking has been your ability to follow what's being said to you.

That's the point. I've achieved the goal of having rest frames at different velocities without having differences in acceleration.

Yes I can.

Look, the hypothesis that has been advanced is that acceleration, not relative velocity is responsible for the differences. According to that hypothesis, hypothesis if both twins are subjected to the same acceleration for the same amount of time they should age by the same amount. My setup disproves that by subjecting the twins to equivalent amounts of acceleration for the same amount of time and coming back with different amounts of elapsed time.

By canceling the acceleration off the bat, you fail to prove that acceleration plays no role.
Do you understand your error in logic? Do you understand how your setup lacks?[/QUOTE]

10. OnlyMeValued Senior Member

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If one twin experiences 1g and no velocity, i.e. remains at rest on Earth (the stay at home twin), the other twin (the traveling twin) constantly experiences 1g of acceleration for the entire time he is traveling, and when they are reunited the traveling twin has aged less, it cannot be in anyway attributed to the acceleration, which remains the same for both twins throughout the traveling twin's journey.., and must be the result of the traveling twin's "rms velocity" relative to the stay at home twin.

What is wrong with this logic?

11. RJBeeryNatural PhilosopherValued Senior Member

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I'm sorry Trippy but even with that distinction I don't see how we can claim displacement (aka distance with direction) over time occurs for either the twins in different gravity wells or the twins at different ends of an accelerating rocket ship.
I personally think it's more natural to say that you must accelerate a body in order to give it a velocity, but I'm not convinced we can say either one truly "comes first".
First of all, perhaps you should just formally define relative velocity. The reason is that I can define acceleration in ways that do not involve relative velocity.

Point being: On one hand, we have relative velocity without acceleration (in the Third Brother scenario, for example). We'll just accept the notion that it's possible without worrying about how they got that velocity in the first place. On the other hand, we also have acceleration without relative velocity in the two scenarios currently being discussed. In the velocity-without-acceleration scenario we cannot conclude unambiguous time dilation; in the latter two acceleration-without-relative-velocity we can conclude unambiguous time dilation.

While I don't ask you to agree, would you consider admitting that my logic is not completely faulty?

12. arfa branecall me arfValued Senior Member

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That doesn't make much physical sense.
Changes in velocity = accelerations; all velocities are relative.

I don't see how you can physically accelerate a frame of reference without changing its relative velocity. Should I be paying more attention? Is there a difference between accelerating a frame and defining its relative velocity?

13. TrippyALEA IACTA ESTStaff Member

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I understand your point, I'm not sure I agree with it. I need to think about what you're saying some more, because it seems like it has more to do with the relativity of simultaneity than anything else.

Have you considered Tach's suggestion - accelerating two identitical clocks at different rates to the same speed (in an arbitrary rest frame)?

Also, have you considered somethign I suggested a while ago in any further depth? That while they might not agree on the magnitude, there are still things that all three twins can agree on?

14. TachBannedBanned

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Nope, you are missing the point, in order to demonstrate that acceleration plays no role, you cannot cancel out the acceleration. The point of the experiment/exercise is to prove that the aging differential is a function of velocity differential and not a function of acceleration, remember? By canceling out the acceleration effects, you fail to prove what you've been trying to prove.

Precisely, see above.

Incomplete statement, this is where your error lies. The correct statement is:
" if both twins are subjected to the same acceleration for the same amount of time IN THE ABSENCE OF ANY OTHER DIFFERENCES (aka DIFFERENCE IN SPEED) they should age by the same amount.

But you are applying a DIFFERENCE IN SPEED IN ADDITION to the acceleration. Therefore, any person versed in physics will immediately point out that your problem statement is violated in the very experiment you are attempting to set up.

And your "setup" violates your (incomplete) problem statement, thus disproving your conclusion.

Last edited: Dec 17, 2011
15. RJBeeryNatural PhilosopherValued Senior Member

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Yes, Arfa Brane, we're discussing how EEP relates to the problem.

1) Clock A on a large, unrotating mass while clock B resides in the dead of space.
2) Clock A at the nose of a constantly-accelerating rocket ship while clock B resides in the tail.

Both scenarios involve unambiguous time dilation, as well as "acceleration" via EEP, but the displacement between clocks does not change; therefore I am claiming it is difficult to make the case that relative velocity is required for unambiguous time dilation.

16. TachBannedBanned

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This is the correct experimental setup that completely refutes RJBeery's ideas.

17. TachBannedBanned

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The falsity of your claims has been proven multiple times in this thread. Read again here. Learn a new mantra: "acceleration plays no role, it is all in the speed".

18. RJBeeryNatural PhilosopherValued Senior Member

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Please remember I cannot read Tach's posts. Also, on first blush I'm not sure what the point of this would be. In order to establish unambiguous time dilation you would need 2 co-location events and that is not possible if their acceleration was all in the same direction. Even so...I still don't see what we think it might show us.

19. RJBeeryNatural PhilosopherValued Senior Member

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Could you tell me what those things might be, specifically? Because this runs contrary to my beliefs. I have to say though...it's nice to finally have some debaters with enough balls to put substance in their posts.

20. TachBannedBanned

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Yes, you can. You can also read this.

The point is to show that your fringe ideas are easily refuted by simple application of basic physics.

You sure about that ?

Please Register or Log in to view the hidden image!

It will show that you have been wrong for about 400 posts.

Physics ain't religion. There is no place for "beliefs" in physics.

Last edited: Dec 17, 2011
21. TrippyALEA IACTA ESTStaff Member

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The only thing that is failing in any of this is your comprehension of the setup in the first place.

It has been consistently deficient and has lead to page after page of distracted discussion based on your misperceptions of the discussion.

This is another such event. You're grasping at straws desperately trying to find something to be right about because you have so much emotional currency invested in being right - all of the abuse you've handed out. On the other hand, I have precisely zero emotional currency invested in being right.

Even now you still can't comprehend how demonstrating that the effect still occurs with the alleged causal mechanism removed from the equation disproves the hypothesis.

If I hypothesize that A is neccessary for B to occur, and I can demonstrate B happening without the influence of A then I have disproven the hypothesis.

Precisely, see above.

It's implicit in the statement, and if you had been paying attention you would know that, because if you bothered to actually read what anybody else had to say, you would have realized that I have addressed precisely that already, when I talked about the reason why although the accelerations are equivalent, the frames are not.

There is no difference in acceleration. The acceleration is equivalent in both cases.

22. OnlyMeValued Senior Member

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Tach, just for information purposes. I just checked out the ignore function and RJ if he has put your name in his ignore list cannot see any of your posts past or current.

The post numbers remain the same but some are missing.....

BTW I don't put anyone on ignore. I was just confirming his statement.

So unless someone else quotes you he can't see what you post.

23. OnlyMeValued Senior Member

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This is a very good example where sticking to a single construction of a hypothetical is of value, at least up to the point where some consensus can be established.