Found a way around relativity of simultaneity

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Discussion Overview

The discussion centers around the relativity of simultaneity as described in the theory of relativity, particularly through a thought experiment involving a train and lightning strikes. Participants explore modifications to this thought experiment, questioning the nature of simultaneity and the implications of faster-than-light signaling.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant proposes a modification to the thought experiment using ropes to argue for an absolute sense of simultaneity, claiming that the instantaneous nature of the rope's movement could imply simultaneous events.
  • Another participant points out that the idea of instantaneous signaling contradicts established physics, suggesting that all segments of the rope do not react simultaneously.
  • A different participant questions the assumption that no object can travel faster than light, proposing the idea of using an instantaneous signal to indicate lightning strikes.
  • Several participants challenge the feasibility of instantaneous signaling, emphasizing that nothing can travel faster than light and referencing a FAQ that addresses common misconceptions.
  • One participant discusses the implications of the speed of the pulling wave in relation to the train observer and platform observer, suggesting a paradox in their observations of simultaneity.
  • Another participant emphasizes that relativity of simultaneity is a consequence of the finite speed of light, not a premise used to prove it, and offers a nuanced view on the relationship between these concepts.
  • Some participants advise caution when challenging established scientific principles, suggesting that one should first consider the possibility of error in their reasoning.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the nature of simultaneity and the implications of faster-than-light signaling. There is no consensus on the validity of the proposed modifications to the thought experiment or the interpretations of simultaneity.

Contextual Notes

Limitations in the discussion include unresolved assumptions about the nature of signaling, the dependence on definitions of simultaneity, and the complexities of transforming observations between different reference frames.

  • #31
left rope event occurs at (0.75, -1.25) in train frame and perceives at (12.5, -7.5). So, to travel (- 1.25 - 7.5) = 8.75 spatial distance with 0.53 speed requires 16.51 sec.
-7.5 - (-1.25) = -6.25
 
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  • #32
Ich has pointed out what I was going to. ( I had a longer reply ready but then lost it).

You transposed the distances traveled by the wave.

The left wave travels a distance of 6.25 ls at a speed of ~0.53c, which takes 11.75 sec (after correcting for the rounding error introduced by the inaccurate value for the speed.)

And in turn, the right wave travels 8.75 ls at a speed of ~0.66c, which takes 13.25 sec (after making the same rounding correction.)

Using the correct values you get the same answer as above. The right wave leaves at -0.75 sec, and the left leaves at 0.75 sec, and both reach the platform at 12.5 sec according to the rest frame of the train.
 
  • #33
Ok, so that is the error. I am very sorry for that.

The calculation perfectly shows 0.75 for left event and -0.75 for right event.

I have checked the maths by putting watchmen in both frame. Both observer sees that platform ropes meet at platform observer simultaneously and both observer sees that train ropes meet at train observer unsimultaneously if the events is simultaneous in platform frame and unsimultaneous in train frame.

Thanks to all.
 

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