The universe is expanding --except where electromagnetic or gravitational forces "prevent" it.
So how far from, say, a galaxy would one have to be to observe the expansion -- and would it occur, at the Hubble rate abruptly, or progressively?
Added (1). A point of clarification: What I'm getting at here is that at the outer edge of a galaxy, we seem to believe that space is not expanding due to the effect of the gravitational force-- but that at some point away from the edge of the galaxy, space /universe is expanding. Is that transition abrupt or progressive up to the Hubble constant?
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