Universal Regeneration: Is Expansion Recycled?

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Discussion Overview

The discussion explores the nature of the universe's expansion, questioning whether it expands in the same physical location after a collapse or if it exists within empty space. Participants delve into concepts of vacuum, dimensionality, and the implications of a finite universe.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that the universe may always expand in the same physical location after a collapse, while others question if it simply floats through empty space.
  • One participant asserts that the universe is not typically embedded in a higher-dimensional space and that the surrounding empty space is part of the universe.
  • A question arises regarding the nature of "empty space," with some participants differentiating between free space that can be occupied and the concept of "nothing."
  • Another participant emphasizes that the vacuum, as understood in quantum field theory (QFT), is indeed something, prompting further inquiry about what exists beyond this "something."
  • It is suggested that the universe can be finite without requiring anything beyond it, using the analogy of a sphere's surface, which is finite yet has no boundaries.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the nature of the universe's expansion and the concept of empty space, indicating that the discussion remains unresolved.

Contextual Notes

Participants have not reached consensus on the definitions of empty space or the implications of a finite universe, leaving several assumptions and interpretations open for further exploration.

alexkerhead
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Is it possible that maybe the universe always expands in the same phsical place every time it expands, after collapse?
Or is the only viable theory that the universe floats through empty space?
I know this is a dumb question, but please, any insight is useful.
 
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alexkerhead said:
Is it possible that maybe the universe always expands in the same phsical place every time it expands, after collapse?
Or is the only viable theory that the universe floats through empty space?
I know this is a dumb question, but please, any insight is useful.

The universe just is, we don't usually embed it in a higher dimensional space. The empty space around us is part of the universe.
 
SpaceTiger said:
The universe just is, we don't usually embed it in a higher dimensional space. The empty space around us is part of the universe.

Do you mean with empty space a free space that can be occupied or do you mean: empty space = nothing ?
tks
 
Pippo said:
Do you mean with empty space a free space that can be occupied or do you mean: empty space = nothing ?

I mean the vacuum, which, in QFT, is most certainly something.
 
SpaceTiger said:
I mean the vacuum, which, in QFT, is most certainly something.
As the universe is not infinite what is there after the "something"?
 
There doesn't need to be anything else out there - not even some "emptiness" - for the universe to be finite. It doesn't need a boundary. Consider the surface of a sphere: it has no boundaries, yet is finite.
 

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