Do we move in the Universe? Or is everything stationary

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Discussion Overview

The discussion revolves around the concept of motion within the universe, questioning whether anything can be said to move according to the universe itself or if all motion is relative to other bodies of mass. Participants explore the implications of the universe's expansion and the absence of a definitive reference point for measuring motion.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that motion can only be defined relative to other objects, suggesting that without a reference point, the concept of movement is meaningless.
  • One participant argues that the universe is expanding from every point and that we can only track our movement relative to other masses, implying that we do not move in the universe itself.
  • Another participant emphasizes that to claim no movement exists, a reference point is necessary, indicating that movement is undefined without it.
  • Some participants express confusion about the meaning of moving "according to the universe," suggesting that such a question lacks meaning without a fixed reference frame.
  • There is a discussion about whether the lack of motion can be considered a form of motion, with participants debating the nature of movement and reference frames.

Areas of Agreement / Disagreement

Participants generally agree that motion is relative and cannot be defined without reference to other bodies. However, there remains disagreement about the implications of this for understanding movement within the universe itself, with some asserting that motion cannot be proven without reference points.

Contextual Notes

Participants highlight the limitations of defining motion without a definitive reference point, which complicates the discussion of movement in the universe. The conversation reflects various interpretations of motion and the challenges of discussing it in an absolute sense.

  • #31
I was was not including the interference of gravity, but I like the discussion. I was more leaning towards the frame of reference of each body of mass to the universe.
 
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  • #32
Jaami M. said:
I was more leaning towards the frame of reference of each body of mass to the universe.

I think the point of the previous discussion is that there is no such thing in any absolute sense. We can construct reasonable definitions of what it means to be "moving with respect to the universe" (for example, vanhees71's suggestion that "moving" means "not seeing the CMBR as isotropic"), but no one of them can be singled out as "the" definition of what it means to be "moving". It all depends on your choice of coordinates and what problem you are trying to solve.
 
  • #33
Jaami M. said:
I was was not including the interference of gravity, but I like the discussion. I was more leaning towards the frame of reference of each body of mass to the universe.

Then in this context, the answers you got from previous posters are correct. My thought process only applies to your experiment where i take into account the gravity of the masses.

I was never against what PeterDonis was suggesting, he is writing in the context of reality. Which i agree is in the spirit of the forum. I just found the idea that i suggested interesting to think about.
 
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