Is Time Constant? Why We Assume It Is

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Discussion Overview

The discussion explores the assumption of time's constancy, questioning how we can be sure that time has passed at the same rate throughout history. It touches on theoretical implications and conceptual understanding of time in relation to astronomical measurements.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions the assumption of time's constancy, suggesting that time could have varied in speed in the past compared to now.
  • Another participant references a book, "Relativity Simply Explained," indicating that there is a discussion on this topic within its first chapter.
  • A different viewpoint suggests that if time were to speed up or slow down uniformly everywhere, it would be imperceptible to observers, as all processes would be affected equally.
  • One participant presents a hypothetical scenario where time has slowed down significantly, yet the perception of time remains unchanged due to synchronized effects on biological and mechanical processes.

Areas of Agreement / Disagreement

Participants express differing views on the nature of time and its constancy, indicating that the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

The discussion includes speculative scenarios and assumptions about the nature of time that are not universally accepted or verified.

larrym3
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Why is it generally assumed that time is and has been constant? When a star is described as being 150 million light/years away - how do we know that the time during those years passed at the same rate as time now. Couldn't time have been faster (or slower) in the past?
 
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There is a good discussion of this in the first chapter of Relativity Simply Explained, by Gardner.
 
If time goes faster/slower everywhere then time is still going as fast everywhere, you wouldn't notice the difference.
 
I agree with DLuckyE, I think the question as posed is experimentally meaningless.

Let's suppose that we are some uber godlike beings watching poor humans carry out their limited measurements of time. We can tell that time has "really" slowed down by a factor of 2 since yesterday. Because the time for biological process slowed down everyone is really waking up late for their meetings, but because the time for alarm clocks slowed down nobody is rushing (any more than normal). They look out the window and because time slowed down for the solar system the day looks normal. I could go on, but I think you get the idea.
 

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