Is my understanding of relativity correct?

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Discussion Overview

The discussion revolves around the understanding of relativity, specifically special relativity (SR) and general relativity (GR). Participants explore concepts related to inertial frames, the speed of light, and the interpretation of motion through spacetime.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant describes a scenario involving two observers moving apart at constant velocity, suggesting that each can consider itself at rest relative to the other, but this is challenged by others.
  • Some participants express confusion over the terminology and concepts used, indicating a need for clearer explanations based on basic principles of SR.
  • There is a discussion about the constancy of the speed of light (c) in inertial frames, with agreement that it remains constant regardless of the observer's frame.
  • One participant questions the behavior of light in rotating frames, leading to a discussion about whether the speed of light changes in such frames.
  • Another participant asserts that while the speed of light is constant in vacuum, it may appear to change in a rotating frame, prompting further clarification on this point.
  • There are critiques of the clarity and coherence of the initial participant's explanation, with suggestions for using more comprehensible language.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and clarity regarding the concepts of relativity. There is no consensus on the initial participant's explanation, with some finding it unintelligible while others attempt to clarify and correct the statements made.

Contextual Notes

Some participants note limitations in their understanding of the terminology and concepts of SR and GR, indicating a reliance on layperson-targeted resources. There are unresolved questions regarding the interpretation of motion and the behavior of light in different frames.

Rotating Frame
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Okay I am new to relativity. I have been reading some books. Let me see if I understand this correctly. Consider the following scenario. There are 2 observers or inertial fames. They are moving apart at a constant velocity. Each ovserver can consider itself at rest relative to the other. Observers move through spacetime at the speed of light. In each relative frame the following can be considered true. Motion is converted from the time dimension into space through adjacent frames of symmetry, so that each observer can consider the other as falling over a sort of horizon as frames transate. These distortions are from the perspective of each observer a sort of fleshing out of an underlying symmetry in which mirror images or probability zones can be considered equal even though they are kind of negative opposite. Sorry if I am not very coherent, but am I on the right track?
 
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I may not be up to speed on SR and GR like many here, but I think I know a little bit about the basics, and I literally have no idea what you are trying to say after about halfway down. Start with JUST basic SR and use terminology JUST from there.
 
Drakkith said:
I may not be up to speed on SR and GR like many here, but I think I know a little bit about the basics, and I literally have no idea what you are trying to say after about halfway down. Start with JUST basic SR and use terminology JUST from there.

Sorry I don't know all the terms, I am hoping to learn by being corrected. I have only read a few layperson targetted books that use analogies to describe the theories. I am not even sure I understand the difference between SR and GR. SR is a kind of 'freeze frame' or contour line of symmetry (sorry only basic math here) within the greater framework of GR in which the speed of light remains constant no matter where it is observed from in those frames? Sorry if this is confusing.

Edit: nvm I know I am getting this wrong because the speed of light remains constant from all frames in SR and GR right?
 
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Yeah, light always travel at c in any inertial frame.
 
Drakkith said:
Yeah, light always travel at c in any inertial frame.

And any rotating frame?
 
Rotating Frame said:
I am hoping to learn by being corrected.

This is a very bad strategy and we discourage it. It's inefficient, and it tends to annoy the people doing the correction. It also puts all the effort on their part, as opposed to yours.
 
Rotating Frame said:
There are 2 observers or inertial fames. They are moving apart at a constant velocity. Each ovserver can consider itself at rest relative to the other.
No, if they are moving apart at a constant velocity then they are movinig relative to the other. They can each consider themselves at rest, but not at rest relative to the other.

Rotating Frame said:
Motion is converted from the time dimension into space through adjacent frames of symmetry, so that each observer can consider the other as falling over a sort of horizon as frames transate. These distortions are from the perspective of each observer a sort of fleshing out of an underlying symmetry in which mirror images or probability zones can be considered equal even though they are kind of negative opposite. Sorry if I am not very coherent, but am I on the right track?
This is completely unintelligible. Are you perhaps not an english speaker and using some sort of machine translation tool?
 
Rotating Frame said:
And any rotating frame?

am i correct in answering this with:
No, a rotating frame is not inertial thus c will change constantly in this rotating frame
 
laurub said:
am i correct in answering this with:
No, a rotating frame is not inertial thus c will change constantly in this rotating frame
Yes. This is essentially correct, although I would say the speed of light is changing, rather than c.
 
  • #10
yes, ofcourse, c is an agreed upon value describing the speed of light in vacuum.
It is the speed of light that is constantly changing in a rotating frame, not the value of c.
thank you.
 
  • #11
laurub said:
yes, ofcourse, c is an agreed upon value describing the speed of light in vacuum.
It is the speed of light that is constantly changing in a rotating frame, not the value of c.
thank you.
No worries, it was a very minor point, and it seems like you understand the major points.
 
  • #12
Rotating Frame said:
am I on the right track?

No. I'm sorry, but what you wrote is simply word salad. And there's no need for it. Relativity can be described and understood using everyday comprehensible language. I suggest taking a look at the book "It's About Time" by N. David Mermin.
 

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