Speed vs. time for our Galaxy and an Observer

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Discussion Overview

The discussion revolves around the effects of relative motion on time perception, particularly in the context of an observer moving in relation to the Earth, solar system, and galaxy. Participants explore the implications of different frames of reference and how they influence the understanding of motion and time.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose a hypothetical scenario where the Earth, sun, solar system, and galaxy are moving at 1,000,000 mph due north, questioning how this affects an observer traveling due south at the same speed.
  • There is a discussion about frames of reference, with some arguing that in the solar system's frame of reference, the observer would be stationary, while others assert that this is an arbitrary choice and that motion is relative to different frames.
  • One participant introduces a tongue-in-cheek theorem about the center of mass of the Universe being at absolute rest, questioning the implications of motion on this concept.
  • Another participant emphasizes the symmetry of time perception, stating that each observer sees their own clocks as normal while perceiving others' clocks as ticking slow, and argues that this does not lead to a contradiction.

Areas of Agreement / Disagreement

Participants express differing views on the implications of relative motion and the nature of frames of reference. There is no consensus on how these factors affect time perception, and the discussion remains unresolved.

Contextual Notes

Participants rely on hypothetical scenarios and assumptions about motion and frames of reference, which may not be universally accepted or defined. The discussion does not resolve the complexities of these concepts.

zuz
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Lets just say for the sake of argument that the earth, sun, solar system, galaxy were all moving due north at 1,000,000 miles an hour. If you were to travel due south at 1,000,000 mph you would basically be not moving at all. How would this affect time for you or anyone observing you?
 
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zuz said:
Lets just say for the sake of argument that the earth, sun, solar system, galaxy were all moving due north at 1,000,000 miles an hour. If you were to travel due south at 1,000,000 mph you would basically be not moving at all. How would this affect time for you or anyone observing you?
Yes, there is a frame of reference such that if the solar system were moving at N mph in one direction and you were moving at N mph in the opposite direction IN THE SOLAR SYSTEM'S FRAME OF REFERENCE you would be stationary in the first FOR. So what? That's how motion works.

EDIT: If you mean that the solar system and you are moving in the SAME frame of reference then your statement that you would not be moving makes no sense, as that is NOT how motion works.
 
phinds said:
That's how motion works.
There is also this (tongue-in-cheek) theorem

Theorem
The center of mass of the Universe is at absolute rest.
Proof (reductio ad absurdum)
If it moved, where would it go?"
 
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zuz said:
Lets just say for the sake of argument that the earth, sun, solar system, galaxy were all moving due north at 1,000,000 miles an hour.
You're just picking an arbitrary frame of reference here, but ok.
zuz said:
If you were to travel due south at 1,000,000 mph you would basically be not moving at all.
No, you'd be stationary in the frame of reference you chose arbitrarily earlier. In all other frames you're moving.
zuz said:
How would this affect time for you or anyone observing you?
Just the same as always. Your clocks look normal to you and everyone else's (well, those in motion relative to you) tick slow. Everyone else says their clocks look normal and yours tick slow. It's symmetric. No, that's not a contradiction.
 
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