[Ethos]

This concept has always given me trouble. On the one hand, we estimate the age of the universe to be approx. 13.7 billion years old. That translates into a universe with a total volume of fantastic size while beginning its existence as infinitely small. With expansion approaching the speed of light and increasing, by some estimates, one needs to ask; What is it that is expanding? We know that space is a structure and while some people wish to define it as nothing, most of us are aware that a structure can't be defined as nothing. This leads me to ask the question:

If space is expanding, does that mean that the space between particles is also following suit? Or; Is it only expanding where gravity and the electro weak and strong forces prevents it from doing so?

[MOD EDIT - please phrase your post titles as questions as this makes it easier for users to identify items of interest and also results in more responses over time. Thanks.]

[Soul Surfer]

Yes it IS space itself that is expanding.  That is why it is possible for things to "vanish over the edge"  by expanding away from us at faster rates than the speed of light.  This is why we do not yet (and may never know for sure)  the true size and shape of our universe. Currently this expansion with distance is too slow to show up at any distance less than that of large clusters of galaxies or affect the motions of planets stars and galaxies  although the theoretical expansion of for example the orbit of the earth is a small and not measurable but non zero amount in a year.

[Vern]

I suspect that the notion that nothingness, empty space, can expand was accepted when it seemed certain that Einstein's General Relativity was successful. The idea of variable space-time became popular because of Einstein IMHO, and still is popular among most folks who ponder the most basic realities of the universe. But that notion is a great obstacle to understanding the true cause of these same basic realities.

If you disallow variable space-time, the true cause of relativity phenomena quickly becomes obvious. H Ziegler explained this to Einstein in 1909. 

[Ethos]

The idea of variable space-time became popular because of Einstein IMHO, and still is popular among most folks who ponder the most basic realities of the universe.
 

If this is truly the case, then couldn't one also presume that the very space between particles themselves is also expanding? Even though this would be virtually nondetectable by current standards of measurement. If space is expanding, then one would have to assume that this space was also doing the same.

[ScientificBoysClub]

Yeah u can say space is expanding as distortion in space is expanding !!

[Raghavendra]

even the energy is spliting all the sides in the universe....They can be destructive

[irish del]

I wonder if the space between the stars ,planets and galaxies are expanding relative to there mass or does it expand evenly through out space irrespective of the gravity they exert?

[Ethos]

 The idea of variable space-time became popular because of Einstein IMHO, and still is popular among most folks who ponder the most basic realities of the universe. But that notion is a great obstacle to understanding the true cause of these same basic realities.

Absolutely Vern; It seems to me that if we limit this explanation to the effect that speed and gravity have on the volume or physical displacement of matter itself, one can clear up much confusion. Why it seems for the Physicist, less complicated to visualize space and time as variant, and then suggest that matter is invariant is like; Strainig at a knat and being willing to swallow a camel.

[Vern]

This is especially true Ethos, when we consider that we know the cause of the distortion of matter. There is no cause that can explain the distortion of space and time. The cause of the distortion of matter is that it is composed at its elementary level of stuff that must always move at the invariable speed of light.