Questions about Universe expansion

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The discussion addresses two key questions about the expansion of the Universe. First, local gravitational fields are strong enough to prevent expansion at stellar and galactic levels, effectively canceling out the expansion due to gravity. Second, scientists acknowledge that observations of the expanding Universe reflect events that occurred nearly 14 billion years ago, which is crucial for understanding cosmic expansion. The conversation also clarifies that while Earth is at the center of the Observable Universe, this does not imply a special status, as all points in the Universe can be considered central to their own observable regions. Overall, the expansion of the Universe is a complex interplay of gravity and the finite speed of light.
AlSo
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I have two questions about the expansion of the Universe. 1. Why is there no local expansion around us, is local gravitational field strong enough to prevent this? How does the vector of gravity act to prevent expansion in multi-directions? 2. When scientists observe the expanding Universe, and comment that "further Universe expands even faster", have they considered the fact that what they see "at the edge" had actually happened nearly 14 billion years ago? Thank you.
 
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1) Yes you are correct. Theoretically universe expansion holds on all levels, but any expansion on the stellar, or even close galactic level is canceled out by gravitational attraction.

2) Yes they do.
 
thanks Vorde!
 
thanks phinds, that is very useful. I always feel uneasy when I hear scientists say "the farther Universe expands faster"----this seemed to commit the same mistake we made centuries ago----placing the Earth at the centre of the Universe. Cheers!
 
AlSo said:
thanks phinds, that is very useful. I always feel uneasy when I hear scientists say "the farther Universe expands faster"----this seemed to commit the same mistake we made centuries ago----placing the Earth at the centre of the Universe. Cheers!

The Earth is at the center of the Observable Universe but this doesn't imbue it with any preferential frame - all points are at the center of their own observable universe - due to the expansion of the Universe and the finite speed of light.

The furthest places we can "see" do appear to be accelerating away from us but in actuality it is just the consequence of a scale factor over a bigger area of space - its quite a logical assumption.
 
thanks Cosmo Novice!
 
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