Questions about the increase with time of distance between two distant points in the Universe.

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11
votes
2answers
371 views

Space expansion in layman terms

So far I got to understand the expansion of space is not to be understood as stars drifting further apart through space. There's something more fundamental - e.g. you can't simply measure speed of it, ...
12
votes
1answer
183 views

On what scale does the universe expand?

According to the theory (or my understanding of it), the universe is not only expanding, but speeding up. If the galaxies are moving apart, are the solar systems within them also moving apart from ...
1
vote
2answers
148 views

Contradict the expansion of the universe?

Lets say that we observe in a distant galaxy cluster, which in all the galaxies move far away from us. and here we see in the same cluster a galaxy that move away from us in a much lower velocity ...
4
votes
6answers
191 views

How can an infinite universe expand?

I understand the expansion of the universe as actually an increase in the ratio of space to matter. Is this a correct understanding? Otherwise, I don't understand how an infinite structure can ...
4
votes
1answer
114 views

Does the universe expand at the same rate everywhere in the universe?

Specifically, I am wondering if some areas of the universe expand faster than other areas and whether the faster expanding areas diffuse the expansion through the slower expanding areas or does the ...
3
votes
1answer
126 views

Evolution of the Hubble parameter

In the lambda-CDM model describing an accelerating Universe, the Hubble parameter is currently decreasing with time. Will it continue to decrease forever?
3
votes
1answer
98 views

Dark Energy Expansion

The new Cosmos extra features mentions that at about 6,771,500,000 years ago the universe began an accelerated expansion. How do we know this? What evidence do we have for this renewed and accelerated ...
2
votes
1answer
103 views

Are galaxies moving away with constant acceleration?

Suppose that we could measure the current acceleration with respect to us of a distant galaxy chosen at random in our observable universe (Ignore the peculiar motion of the galaxy). Is the ...
2
votes
2answers
151 views

Conundrum involving distance to object, universal expansion, age of universe, etc

I was recently reading about a galaxy or quasar (not sure which, so lets just say quasar) where the estimated distance to this thing was some very significant fraction of the age of the universe. ...
1
vote
2answers
52 views

Expansion of Space

If Space is expanding between the Galaxies then why isn't it also expanding between the Stars within the Galaxies as well ? In fact why isn't Space expanding within our Solar System ?
1
vote
3answers
101 views

What do we mean by space is expanding?

I know this question had often been asked on Physics.SE as well as this site but I don't get them. What do mean when we say that space is expanding? I mean that space is no physical entity that can ...