Do we know how many meters long one second is?

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Discussion Overview

The discussion revolves around the relationship between time and length, specifically how many meters correspond to one second in the context of a particle at rest. It explores theoretical implications and interpretations of world lines in spacetime.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant states that the world line of a particle at rest for one second can be expressed as the product of the speed of light and time, leading to a length of approximately ##3 \times 10^{8} \ m##.
  • Another participant suggests that this implies we pass through time at the speed of light, but cautions that this interpretation is limited and can lead to confusion.
  • A later reply emphasizes that while the statement about passing through time at the speed of light has some validity, it should not be taken too far without careful consideration.

Areas of Agreement / Disagreement

Participants express differing views on the implications of relating time to the speed of light, with some agreeing on the mathematical relationship while others caution against overextending the interpretation.

Contextual Notes

Some assumptions about the nature of time and space may not be fully articulated, and the discussion does not resolve the potential confusion surrounding the implications of the speed of light in this context.

student34
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TL;DR
Do we know how many meters long one second is?
In other words, how many meters long is the world line of a particle at rest for 1 second?
 
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student34 said:
Summary:: Do we know how many meters long one second is?

In other words, how many meters long is the world line of a particle at rest for 1 second?
The conversion factor from time to length is the speed of light. For an object at rest in some IRF for proper/coordinate time ##t##, the worldline has length ##ct##.

If ##t = 1s##, then the length of the worldline is approximately ##3 \times 10^{8} \ m##.
 
Possibly illuminating:
 
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I guess this means that we pass through time at the speed of light. Interesting.
 
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student34 said:
I guess this means that we pass through time at the speed of light.
While there is a sense in which this is true, it is a very limited sense and you can't really draw any useful inferences from it. We have had a number of previous PF threads dealing with the confusion caused by taking this statement too far.
 
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