Is it impossible to separate a distance of 1light hour in space?

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Discussion Overview

The discussion revolves around the feasibility of separating a distance of one light hour in space, particularly focusing on the perspectives of two observers moving apart and measuring distances using laser signals. The scope includes conceptual and theoretical considerations of relative motion and measurement in the context of special relativity.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant argues that it is possible to separate two observers by one light hour using laser signals, suggesting that both observers can agree on the distance measured if they are at rest relative to each other.
  • Another participant emphasizes the importance of being at rest relative to each other for accurate measurements, noting that while moving slowly may alter the measurements, they can still approach a state of zero relative velocity.
  • A different viewpoint introduces a scenario involving an object traveling at 90% the speed of light, indicating that the distance measured in the object's frame depends on the timing of the measurement, which was not clearly specified.
  • Some participants express confusion over the conditions of the original experiment and the relevance of statements made from other discussions, suggesting a lack of clarity in the framing of the problem.

Areas of Agreement / Disagreement

Participants do not reach a consensus. There are competing views on whether the distance can be agreed upon by both observers, particularly under different conditions of motion and measurement timing.

Contextual Notes

There are limitations regarding the assumptions made about the observers' states of motion and the timing of measurements, which remain unresolved in the discussion.

Trojan666ru
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Is it impossible to separate a distance of "1light hour" in space?

i was having a debate with a guy on a site and he argues it is impossible to separate such a distance in space.
Suppose two observers A & B they are relatively at rest, A wish to do an experiment so A & B moves apart by sending laser signals, after a huge amount of time, they slows down their speed to get accurate measuremet, A continuously sends a laser beam to B and B does the same. A notices that a laser beam sent to B took exactly 2 hours to return, which means A is now exactly 1 light hour distant apart. B also does this, so B also concludes that he is exactly 1 light hour away from A. They does this until finally they became relatively at rest to each other
Or do they disagree?
When A Calculates exact 1 light hour distance, won't that be 1lhr for B??
His argument was when one of the observers calculate his distance, the other won't get the same measurement because of different frames
Is his argument correct?
Is there really no way to separate a distance in space?
Even i tried saying there is a 1lhr long nebula between these two observers, still he won't agree
 
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I see nothing wrong with your argument. You have specified a valid way to separate two observers by one light hour.
 
It is important to be at rest relative to each other (you can check this via Doppler shifts, for example). If you are, you can measure the distance easily, and both will agree on the value. If you are moving slowly, the measurements will look a bit different, but you can still approach the final state of zero relative velocity.
 
There has been a misunderstanding of the conditions of the experiment, the original question was:

"Consider an object 'O' is traveling towards me at 90% speed of light which is placed at 1hr c away ...".

The distance in the object's frame depends on when it is measured which wasn't specified.
 
GeorgeDishman said:
There has been a misunderstanding of the conditions of the experiment, the original question was:

"Consider an object 'O' is traveling towards me at 90% speed of light which is placed at 1hr c away ...".

The distance in the object's frame depends on when it is measured which wasn't specified.

You seem to be addressing something from some other thread. What you quoted isn't here.
 
phinds said:
You seem to be addressing something from some other thread. What you quoted isn't here.

The original post starts "i was having a debate with a guy on a site ...". I was that guy, the quote is from the other site (a Facebook group). The poster linked this thread in the original thread.
 
Let's continue the discussion in this thread, two threads for the same topic are bad.
 

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