On The Length of a Meter Stick

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Discussion Overview

The discussion revolves around the concept of length measurement in different inertial frames, specifically addressing whether a single meter stick can be perceived as one meter by one observer and less than a meter by another. The conversation touches on the implications of special relativity and the associated paradoxes of length contraction.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that a meter stick can be perceived as one meter by a stationary observer (B) and less than a meter by a moving observer (A), suggesting a paradox.
  • Others argue that this situation is a standard length contraction scenario explained by special relativity, where length is frame-dependent.
  • One participant asserts that the differing measurements do not constitute a self-contradiction, emphasizing the relativity of simultaneity and the nature of measurements in different frames.
  • Another participant questions the paradox and seeks clarification on why it is considered paradoxical, suggesting that the explanation has not been adequately provided.
  • Some participants express frustration over the perceived lack of understanding of special relativity among others in the discussion.
  • A later reply reiterates that a meter stick measures length in the frame where it is at rest, implying that it does not have to be one meter in moving frames.

Areas of Agreement / Disagreement

Participants do not reach a consensus; multiple competing views remain regarding whether the differing measurements represent a paradox or a misunderstanding of special relativity.

Contextual Notes

Some limitations include the dependence on definitions of length and the assumptions about the observers' frames of reference. The discussion does not resolve the mathematical implications of the claims made.

DJ_Juggernaut
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Can a single meter stick be one meter per A and less than a meter per B? If so, isn't this is a simple paradox? Does anyone here see it that way?
 
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DJ_Juggernaut said:
Can a single meter stick be one meter per A and less than a meter per B?
What are A and B?
DJ_Juggernaut said:
If so, isn't this is a simple paradox?
Why?
 
A and B are observers in different frames. A is moving, B is stationary relative to the meter stick. B says, the length is one meter. While, A says, the length is less than a meter. This is a simple paradox. Does anyone here see it that way?
 
A.T. said:
Why?
Because A and B give differing answers for the length.
 
This is just your regular length contraction paradox and it is resolved essentially everywhere relativity is discussed in any meaningful manner. You will only think it is a paradox if you do not take into account that space and time mean different things in different inertial frames - including the relativity of simultaneity.
 
DJ_Juggernaut said:
A and B are observers in different frames. A is moving, B is stationary relative to the meter stick. B says, the length is one meter. While, A says, the length is less than a meter. This is a simple paradox. Does anyone here see it that way?

If you don't believe in SR then that's your prerogative. But, there's no point posting here.

This site is for those who want to learn SR, not those who want to dispute it.
 
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Orodruin said:
You will only think it is a paradox if you do not take into account that space and time mean different things in different inertial frames - including the relativity of simultaneity.
Regardless, A and B still give different answers for the length of a meter stick. Is it not self-contradictory to you?
 
DJ_Juggernaut said:
Regardless, the A and B still give different answers for the length of a meter stick. Is it not self-contradictory to you?
Again, you are clearly not even bothering to understand why this is so. If you understood the theory, you would understand that it is not self-contradictory.
 
PeroK said:
This site is for those who want to learn SR, not those who want to dispute it.
I am not disputing it. I am asking whether anyone here sees a self-contradiction here. You can just say NO or YES. I will be on my way.
 
  • #10
So let me ask you this: You have a meter stick parallel to the x-axis. It is one meter in the direction of the x-axis. Now you rotate it 60 degrees and it is 0.5 meters in the direction of the x-axis. Is this self-contradictory?
 
  • #11
Orodruin, you still did not answer my question. If A says, the stick is one meter and B says, the stick is less than a meter. Is it not a self-contradiction?
 
  • #12
DJ_Juggernaut said:
I am not disputing it. I am asking whether anyone here sees a self-contradiction here. You can just say NO or YES. I will be on my way.

I see no contradiction.
 
  • #13
PeroK said:
I see no contradiction.
Okay. So, I send two observes to record the length of a stick and they both come back with different answers and that's not a contradiction. Okay. LOL. I am done.
 
  • #14
DJ_Juggernaut said:
This is a simple paradox.
If it's so simple, why can't you explain what is paradoxical about it?
DJ_Juggernaut said:
Does anyone here see it that way?
No. A meter stick measures length in the frame where it is at rest. In frames where it moves it doesn't have to be 1 meter.
 
  • #15
DJ_Juggernaut said:
Orodruin, you still did not answer my question. If A says, the stick is one meter and B says, the stick is less than a meter. Is it not a self-contradiction?
No, it is not and you refusing to even trying to understand this is quite telling.
 
  • #16
A.T. said:
A meter stick measures length in the frame where it is at rest. In frames where it moves it doesn't have to be 1 meter.
LOL. Okay.
 
  • #17
A.T. said:
If it's so simple, why can't you explain what is paradoxical about it?
Read above, I have already stated my position. I think I get the picture. I don't think anyone here sees a contradiction even though A and B come back with differing answers.
 
  • #18
DJ_Juggernaut said:
LOL. Okay.

You are here to learn, or to just lol at others? What is your point?
 
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  • #19
weirdoguy said:
You are here to learn, or to just lol at others? What is your point?
Oh, I learned alright. I am done with this thread. I am quite satisfied with the responses I got. I thank all who responded.
 
  • #20
DJ_Juggernaut said:
Oh, I learned alright. I am done with this thread. I am quite satisfied with the responses I got. I thank all who responded.

Summary:
Orodruin said:
This is just your regular length contraction paradox and it is resolved essentially everywhere relativity is discussed in any meaningful manner.
A.T. said:
No. A meter stick measures length in the frame where it is at rest. In frames where it moves it doesn't have to be 1 meter.

Thread closed.
 

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