Modest
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]On cosmic scales everything is expanding away from everything else. The simplest way to express such a thing is to put everything on a metric (or a grid, if you like), and to scale the metric. This accomplishes something very specific which I will describe.
If you consider a galaxy such as the Milky Way and measure the speed at which other galaxies are moving away from it then the further the galaxies are, the faster they will be moving away. That is a physical law of astronomy known as Hubble's law.
It is sensible to assume that our position in the universe is not special so that any other galaxy out there also has galaxies receding from it in such a way that the recession velocity increases with distance. An easy way to show this (to model it) is to use a rubber sheet (think of a piece of paper made of rubber). You can mark a bunch of dots on the sheet representing galaxies.
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Maybe you are not yet familiar with how i see the cosmos, as re-stated yet again in post #26 of the "Bang/Crunch Revisited" thread, as follows:
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Our cosmic event horizon is just a small bubble of visibility *within* the thickness of the "rubber" of the good old cosmic expanding balloon. This mini-cosmos within the maxi-cosmos, the Whole Balloon, is cycling through bangs and crunches even as the whole balloon keeps expanding.... *Yes*... out into the infinity of space.
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Anyway, we can't even "see out of the rubber" (the visible cosmos) let alone see the *yes* empty space within or beyond the bubble.
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Modest:
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If you have 4 people each grab a corner of the sheet and stretch it apart then you have effectively modeled the manner in which galaxies move away from one another. One of those dots on the rubber sheet has every other dot moving away from it and the further the other dots are from it, the faster they move away. This is true for any dot.
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The above is a two dimensional rubber sheet... a plane. My expanding balloon is a 3-D sphere... and the "rubber" is the "stuff" of cosmos... with a thickness containing the whole mini-sphere of visibility which is our cosmic event horizon.
So, naturally cosmos appears isotropic/homogeneous in all directions
as the whole balloon expands with our little visible cosmos as one tiny bubble in the rubber of the balloon.
Can you understand what I am saying?
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The expansion of the universe is very similar. Saying "space is expanding faster than the speed of light" means that the distance between two objects on the metric is increasing faster than c. This is an inevitable conclusion given two things:[LIST=1][*]The further away one galaxy is from another the greater the rate at which their distance increases.[*]The universe is infinite in size.
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Space is infinite emptiness. Cosmic "stuff" exists in specific locations within unbounded space.... reference balloon cosmology above.
Nothing... none of this cosmic "stuff" travels faster than light, and space is lack of 'things', emptiness... no-thing-ness, the *volume* in which stuff exists, and "it", being nothing, does not 'travel" or expand at all.
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You're probably wondering what difference it makes if we say something is moving through space or if we say space is expanding between things. And, it indeed does make a difference which can only be revealed by measuring and understanding the apparent motion of cosmic objects. To give one example, if an object is moving away from us *through space* then we expect it to exhibit a redshift which can be calculated with and is due to special relativistic Doppler shift. If, however, space is expanding SR doppler shift will not give the correct redshift results. Cosmological redshift must be used. Wiki summarizes the difference:
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I may introduce a very important criticism of all assumptions surrounding the redshift paradigm, but this is not the "place or time."
I am not "wondering" at all "what difference it makes if we say something is moving through space or if we say space is expanding between things."
It is my most profound understanding that space is empty volume in which all *observable/detectable* phenomena exist and move.
Space is emptiness. It has no properties... being the *void* in which things with properties exist. Space does not expand. Things move away from other things in space... emptiness/volume.
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That quote references "the metric expansion of space" which is a good article at wikipedia. If you want to get a good understanding of just what astrophysicists mean by expanding space then that would be a good place to start.
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I will study it at another time.... and get back to you on prevalent dissent on redshift as the basis for the "inevitable conclusions"... what you believe are indisputable "facts."
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I don't think "volume" is that bad of a word to substitute for "space" in the setting of astronomy and cosmology. We could say that the volume between galaxies increases over time rather than saying the space between them increases. We would also say that the rate at which volume expands is proportional to the volume itself much in the way we would say the expansion of space between objects is proportional to the distance between them. 
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But the reason for more volume between objects over time is that they are simply moving away from each other as in the expanding balloon... not that "space itself" (as if it were an entity) is expanding.
This is your (and "expanding space theorists') fundamental misconception as i see it.
And don't get me started on dilating time again!
Michael
