The metric expansion of the Universe

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The metric expansion of the Universe is a relativistic effect that cannot be measured locally, as it is a concept that applies globally to the universe as a whole. The expansion around the Milky Way is not expected to be faster than that around the Andromeda Galaxy. Hubble's Law describes this expansion, indicating that distances between galaxies increase proportionally to their distance. The cosmological constant acts as a repulsive force, accelerating the expansion over time. Overall, the relationship between these concepts is crucial for understanding cosmic dynamics.
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I have a few questions ragerding this topic. Any help with either question is appreciated.

Is the metric expansion subject to relativistic effects? Will we measure the expansion of space around the Milky Way to go faster than the expansion around the Andromeda Galaxy?

How is the expansion related to the cosmological constant and Hubble's Law? Has anyone been able to derive an expression for the expansion?
 
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Is the metric expansion subject to relativistic effects?
It is an extremely relativistic effect, as it is mostly "speaking of normal things in unfamiliar coordinates". IOW: outside Gerneral Relativity, you couldn't even formulate such a concept.
Will we measure the expansion of space around the Milky Way to go faster than the expansion around the Andromeda Galaxy?
Short answer: most probably no.
Longer answer: You can't measure expansion locally, the concept is useful only globally, if you regard the universe as a whole.
How is the expansion related to the cosmological constant and Hubble's Law?
Hubble's law is simply another ord for expansion of space - distances increase proportional to distance.
The cosmological constant tends to increase the expansion with time. It is a repulsive "force".
Has anyone been able to derive an expression for the expansion?
Yes, http://en.wikipedia.org/wiki/Friedmann%E2%80%93Lema%C3%AEtre%E2%80%93Robertson%E2%80%93Walker_metric" .
 
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