Expansion as Motion: Exploring Space and Ether Theories

In summary: (like air) so it wouldnt be considered as expanding.but if u are talking about the space between galaxies then yes it is expanding.
  • #1
girlwonder
27
0
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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  • #2
Expansion isn't motion.
 
  • #3
Could you explain why please, that's where I'm lost i guess.
 
  • #4
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?
 
  • #5
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.
 
  • #6
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.
 
  • #7
Thanx a bunch.
 
  • #8
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
 

1. What is the expansion of space?

The expansion of space is the theory that the universe is constantly expanding. This means that the distance between galaxies and other celestial objects is increasing over time. This phenomenon was first observed by astronomer Edwin Hubble in the 1920s.

2. How does the expansion of space affect our understanding of the universe?

The expansion of space challenges our traditional understanding of the universe as a fixed and unchanging entity. It suggests that the universe is constantly evolving and expanding, which has implications for concepts such as the Big Bang theory and the age of the universe.

3. What is the role of ether theories in understanding the expansion of space?

Ether theories were once proposed as a medium that fills the entire universe and allows for the propagation of light. While these theories have largely been disproven, they have influenced modern understanding of the expansion of space and the concept of a "fabric" of the universe.

4. Are there any observed effects of the expansion of space?

Yes, the expansion of space has been observed through various astronomical measurements, such as the redshift of distant galaxies and the cosmic microwave background radiation. These observations provide evidence that the universe is indeed expanding.

5. How does the expansion of space impact the motion of celestial objects?

The expansion of space does not directly affect the motion of celestial objects within our own galaxy. However, it can impact the motion of objects in distant galaxies, as the expansion of space can cause them to move away from us at increasing speeds. This is known as the Hubble flow, named after Edwin Hubble who first observed this phenomenon.

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