Expansion of Space: Questions on How the Universe Works

In summary, the two galaxies are not moving through space, the entirety of space between them is physically expanding at a rate of 10 x c.
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Martyn Arthur
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TL;DR Summary
The Expansion of Space Overall Beyond the Visible Universe
I first apologize if this has been posted more than once; sorry.
There is a lack of clarity at my end as to whether I am logged on here?

Say we have two galaxies, the Milky Way (MW) and galaxy A separated along a straight line 20 x the radius of the Universe visible to us.
If I understand correctly then the rate of the physical expansion of space between MW and A could be at the rate of say,
Hi, may I ask a question, please?
Say we have two galaxies, the Milky Way (MW) and galaxy A separated along a straight line 20 x the radius of the Universe visible to us.
The MW is considered a stationary observer.
Then disregarding for the purpose of this any other objects or influences.
If I understand correctly then the rate of the physical expansion of space between MW and A could be at the rate of say, arbitrarily, 10 x c.
I understand that those two galaxies aren't moving through space, the entirety of space between them is physically expanding.
If we then have galaxy D positioned along the same line, just at the edge of our visible Universe which we observe being redshifted relative to the MW at the rate of 1 x c.
Then I understand that the entirety of space between MW and A is expanding at the [arbitrary] rate of 10 x c.
So that the "elastic band" comprising the space between MW and A must presumably be carrying everything within it at the same rate.
So then why then is it that galaxy D is not seen as being redshifted / transported within that "elastic band" away from the MW at 1/2 x 10 x c?
Thinking from another perspective.
If there are two galaxies separated for now along a straight line 200 x the radius of the Universe visible to us.
Is the space between those galaxies expanding at a "commensurate" rate?
If the Universe is infinite does that lad to a concept that the rate of expansion is infinite?
Thanks
Martyn
 
Physics news on Phys.org

What is the expansion of space?

The expansion of space refers to the continuous increase in the distance between celestial objects in the universe. This phenomenon is supported by observations of redshift in the light from distant galaxies, and is believed to be driven by a mysterious force called dark energy.

How does the expansion of space affect the size of the universe?

The expansion of space does not directly affect the size of the universe, as it is a relative increase in distance between objects rather than a physical stretching of space itself. However, it does mean that the observable universe is constantly growing as more distant objects become visible due to the expansion of space.

What is the role of dark energy in the expansion of space?

Dark energy is thought to be the driving force behind the expansion of space. It is a theoretical form of energy that permeates the universe and has a repulsive effect on matter, causing it to accelerate away from other objects. However, the exact nature of dark energy is still not fully understood.

Is the expansion of space uniform?

No, the expansion of space is not uniform. It is believed to be accelerating, meaning that the rate of expansion is increasing over time. This is supported by observations of distant supernovae and the cosmic microwave background radiation.

Will the expansion of space eventually lead to the end of the universe?

It is currently unknown if the expansion of space will eventually lead to the end of the universe. Some theories suggest that the expansion will continue indefinitely, causing the universe to become cold and dark. Others propose that the expansion may eventually slow down or reverse, leading to a potential "big crunch" where the universe collapses back in on itself.

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