Universe expansion faster than light?

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Discussion Overview

The discussion revolves around the concept of the universe's expansion and its relationship to the speed of light. Participants explore whether the expansion can exceed the speed of light, the implications of such expansion, and the distinction between the motion of objects and the expansion of space itself.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions what happens when the speed of the universe's expansion reaches the speed of light, asking if it would remain constant, exceed it, or slow down.
  • Another participant suggests that the speed of light is a limit for objects moving through space but does not apply to the expansion of space itself, proposing that space may have expanded faster than light at some point in the universe's history.
  • A third participant emphasizes that the universe's expansion is already occurring at a rate greater than the speed of light, citing the observation of light from stars over 46 billion light years away despite the big bang occurring less than 14 billion years ago.
  • This participant also notes the separation between the expansion of the universe and the motion of objects within it.

Areas of Agreement / Disagreement

Participants express differing views on the implications of the universe's expansion relative to the speed of light, with no consensus reached on the nature of this relationship.

Contextual Notes

Some assumptions about the nature of space and time, as well as the definitions of speed in the context of cosmic expansion, remain unresolved.

mrxyz
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The speed of light is a constant. Yet the Universe's expansion seems to be getting faster and faster.

So my question is, when the speed of the expansion of the Universe reaches C the speed of light, what happens. Does it remain at that speed? Does it exceed it? Or does it slow down?
 
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As I understand it, the speed of light is the upper limit of the speed of things moving in space and does not limit the speed at which space itself moves. Thus it is possible to conjecture that at some early stage of the universe, space did in fact expand at a speed greater than the speed of light.
 
Google "metric expansion" to explain it all
 
From what I understand, the fabric of the universe is expanding at a rate greater than the speed of light already. We can see the light from stars 46+ billion light years away and the big bang happened less than 14 billion years ago. You would think that the light from the stars 46+ billion light years away would take 46 billion years to reach us therefore disagreeing with how long ago the big bang happened, but the reason we can see the light from those stars is because they used to be much closer.

It's important to note that expansion of the universe and the motion of the objects within the universe are entirely separate concepts.
 

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