Is Expansion Motion and Does It Imply Space as Something?

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The discussion centers on the concept of expansion as a form of motion and its implications for the nature of space. Participants question how space, often considered a void, can exhibit motion if it is not "something." The analogy of an expanding loaf of bread illustrates that as mass expands, the coordinates of its points change, suggesting a form of movement. The conversation also touches on the idea that if nothing exists between particles, the notion of "nothingness" having velocity becomes problematic. Ultimately, the debate highlights the complexity of understanding expansion and its relationship to the fabric of space-time.
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If expansion is motion, and space is expanding, and we consider space as void, how can it then move? Don't we have to consider space as "something" if it moves? If we consider space as "something", doesn't that launch us back to ether theories?
 
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Expansion isn't motion.
 
Could you explain why please, that's where I'm lost i guess.
 
If a mass is comprised of a certain fixed number of points that are assigned co-ordinates and you expand it , the value of these co-ordinates change just like they would if you moved the whole mass over, or up or down.

Also to expand a mass generally involves energy, just like motion.

If i were to watch a loaf of bread expand i could easily say it was moving.

In what way isn't it?
 
It is the grains of the loaf that are moving (away from each other).

If there is nothing between those grains, what meaning is there in saying the "nothingness" has a velocity? After all, we can only measure things.
 
If there is nothing between those grains, what meaning is there in saying the "nothingness" has a velocity? After all, we can only measure things.
If there were nothing between the grains I believe the grains would be touching each other. Space-time is something. Try thinking of time as a one dimensional object. Now you can see that our universe is just a one dimensional duration, and as it expands, we with our view from the inside looking out see this over all motion as space expanding. What we call reality is made up of all the motion in all its different combinations that are confined inside this one duration we call our visible universe, and yes it is filled with space-time.
 
Thanx a bunch.
 
i believe that expansion is a form of motion, but what space r u talking about? if its the space between the particles its not expanding but its being filled by substitutes
 

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