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This isn't quite how I understand the expansion of the universe. The interesting thing is it affects space itself, so the more distance between objects, the mor

This isn't quite how I understand the expansion of the universe. The interesting thing is it affects space itself, so the more distance between objects, the more space there is to expand. This does try to pull stuff apart, but it's quite slow so it doesn't take much to overcome it. Even gravity (the weakest force) is enough to keep stars and galaxy clusters bound together. Atoms are way to small to be affected. This changes if you allow Dark Energy to vary with time, but the paragraph in the article assumes it's constant. > If the work of dark energy were constant over time, it would eventually push all the stars and galaxies so far apart that even atoms could be torn asunder...

empyrrhicist 3y ago
Depends if the expansion is accelerating or not. https://www.youtube.com/watch?v=gEyXTQ9do-c https://www.youtube.com/watch?v=gEyXTQ9do-c
- itishappy 3y ago
  Agreed, and I've edited my comment to include this.
- taylodl 3y ago
  That's not necessarily true. If Dark Energy is a property of the vacuum state of space and it's a force acting opposite of gravity, then the further apart those objects become then the more those objects will accelerate from one another. That's what leads to an accelerated expansion of the universe. That doesn't change the fact that gravity can overcome Dark Energy. To wit, the Andromeda and Milky Way galaxies are on a collision course. Yes, Dark Energy is working to drive those galaxies apart, but gravity is winning and the closer those galaxies get to each other then the strong gravity is going to become. Gravity gets stronger as the distance between objects decreases, Dark Energy gets stronger as the distance between objects increases. That is if Dark Energy is a property of spacetime. Since we don't know what Dark Energy is we can't say for certain, but it appears to be a property of spacetime and if that's the case then this statement is true.

empyrrhicist 3y ago

Depends if the expansion is accelerating or not. https://www.youtube.com/watch?v=gEyXTQ9do-c https://www.youtube.com/watch?v=gEyXTQ9do-c

itishappy 3y ago
Agreed, and I've edited my comment to include this.
taylodl 3y ago
That's not necessarily true. If Dark Energy is a property of the vacuum state of space and it's a force acting opposite of gravity, then the further apart those objects become then the more those objects will accelerate from one another. That's what leads to an accelerated expansion of the universe. That doesn't change the fact that gravity can overcome Dark Energy. To wit, the Andromeda and Milky Way galaxies are on a collision course. Yes, Dark Energy is working to drive those galaxies apart, but gravity is winning and the closer those galaxies get to each other then the strong gravity is going to become. Gravity gets stronger as the distance between objects decreases, Dark Energy gets stronger as the distance between objects increases. That is if Dark Energy is a property of spacetime. Since we don't know what Dark Energy is we can't say for certain, but it appears to be a property of spacetime and if that's the case then this statement is true.