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Comment by asgfoi | Hacker News Reader

The galaxy isn't traveling faster than c away from us, but space is being created in between. So, nothing is actually accelerating, there is no problem, Einstein is still right.

In fact, space is being created everywhere, including yourself and the computer screen. However the amount is so small that you don't notice and local forces nullify the change anyway. With large distances, this amount accumulates, and overwhelms the force of gravity and starts to create the apparent acceleration of distant galaxies away from us. Further explanation from paulddraper: https://news.ycombinator.com/item?id=11068125

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This isn't really correct. Expansion of space is not the same thing as accelerated expansion of space. Aaccelerated expansion is indeed due to something "pushing" objects apart--that something is called "dark energy". But expansion itself, apart from the effects of dark energy, does not push on anything; it doesn't exert any force that moves objects apart or works against gravity. So thinking of ordinary expansion (apart from accelerated expansion) as "creating space" in between objects isn't really correct. It's unfortunate that so many pop science treatments use this way of speaking, since it leads to the incorrect inference I've just described.

The space is expanding and its expansion rate is accelerating. Dark energy is not pushing objects apart, it is causing the acceleration of expansion of space.

What you said isn't even pop science, it is blatantly wrong.

https://en.wikipedia.org/wiki/Metric_expansion_of_space

https://en.wikipedia.org/wiki/Dark_energy

And the money quote:

It is called "dark" because it is not interacting with normal matter, but only with the space time structure.

from http://physics.stackexchange.com/a/206217

> What you said isn't even pop science

What I said was an attempt to explain how the basic model cosmologists use works in layman's terms. It wasn't intended to be "pop science" or even "real science"; that would be building the model, not trying to explain how it works.

The references you give are not "real science" either. Try looking in a cosmology textbook or a peer-reviewed paper. Or, even better, work out the science for yourself instead of arguing from authority.

Yes, this makes sense. If this is the case though, then aren't there some obvious problems with how we think of dimensions (at least the first three or four anyway)?

It seems like creating space to fill the "voids" between particles moving at-what-would-be-faster than the speed of light is like a tesseract for whatever matter is in that rapidly created/expanding space. Unless that space is only accessible to the particles creating it by their relative motion (which still gives us problems with our ideas of dimensions)?

> The galaxy isn't traveling faster than c away from us, but space is being created in between.

That's an intriguing way of phrasing, never thought of it this way. I'm aware that space is expanding, so space must indeed being created in-between.

I'm guessing this space has to contain no energy at all, so it must be made of absolutely nothing, right?

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