What caused us to have relative time

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Discussion Overview

The discussion revolves around the concept of relative time, exploring its physical underpinnings and the reasons behind the lack of absolute simultaneity in time measurement. Participants examine various perspectives on the implications of relativity, the nature of clocks, and the fundamental laws of physics that govern these phenomena.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that relative time arises from the lack of absolute synchronization of clocks, leading to different time interval calculations by observers in different frames.
  • Others argue that the laws of electricity and magnetism inherently lead to the conclusion that light speed is invariant, which contributes to the relativity of time.
  • A few participants question the reasons behind the inability to synchronize clocks absolutely, suggesting that this reflects a deeper issue regarding the nature of simultaneity in the universe.
  • Some contributions highlight the philosophical aspect of asking "why" regarding the laws of physics, noting that such questions often lead to an infinite regress without definitive answers.
  • There are discussions about the implications of light speed invariance and whether it is a sufficient explanation for relative time, with some participants expressing skepticism about its role.
  • One participant raises the idea that the universe's properties might be structured in a way that prevents absolute simultaneity, suggesting that the laws of physics dictate these outcomes.

Areas of Agreement / Disagreement

Participants express a range of views on the reasons for relative time and the nature of clocks, with no consensus reached on the fundamental causes or definitions involved. Multiple competing perspectives remain throughout the discussion.

Contextual Notes

Several participants note that the definitions of time and clocks are crucial to the discussion, indicating that differing interpretations may lead to varying conclusions about the nature of relative time. The conversation also touches on the philosophical implications of scientific inquiry, particularly regarding the limits of explanation in physics.

  • #61
Nugatory said:
All inputs are not symmetrical in the SR version of the twin paradox, which is why it is at least logically possible that conclusion be non-symmetric.

The asymmetry is physically apparent in the fact that the twins experience different acceleration.

It will also show up quite clearly if you just try working the problem in a frame in which the traveling twin is at rest during either the outbound or the inbound leg of the trip (Try it! Don't just take my word for it).

I think sugdub doesn't dispute the twins scenario (because there is asymmetry). What he/she claims is that the symmetric time dilation is not 'real' or 'actual' precisely because it is symmetric.
 
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  • #62
Sugdub said:
You are welcome. Concerning clocks “actually" running slow I precisely mean what physicists indicate in the context of the “twins” thought experiment: the “moving twin”, when coming back, will be younger than the other one, because his/her clock ran slower all along the trip.
Then nature disagrees with you. Clocks do "actually" run slow according to your definition. This experiment has been done many times in many different ways, and the results agree with SR's predictions.

Sugdub said:
My statement is that SR cannot, from a pure logical standpoint, justify that the “moving clock” ran slower: all inputs being fully symmetrical, the conclusion cannot be non-symmetrical.
Your statement is irrelevant for two reasons.

First, it is irrelevant because the assertion that you are attributing to SR is not an assertion that SR makes for inertial clocks. I detailed the assertion that SR actually makes above, and that one is fully symmetrical for inertial clocks. Your objection is therefore simply a strawman fallacy.

Second, it is irrelevant because your definition of "actually" involves an asymmetric situation. So an argument from symmetry simply doesn't apply to whether or not clocks "actually" slow down.
 
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  • #63
PAllen said:
I think sugdub doesn't dispute the twins scenario (because there is asymmetry). What he/she claims is that the symmetric time dilation is not 'real' or 'actual' precisely because it is symmetric.
That isn't what Sugdub mentioned as the definition of "actually".
 

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