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Comment by KMag | Hacker News Reader

Due to accelerating cosmic inflation, some galaxies are receding from us at faster than the speed of light, so their light will never reach us. The majority of galaxies (everything outside of our local cluster, IIRC) will eventually be receding faster than the speed of light and be beyond our vision forever.

Yes, this means most galaxies will appear to actually pass through/into the cosmic background, from our point of view.

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I thought the logic of inflation had no limit, and eventually, everywhere, even atoms themselves would come apart.

I don't think we understand enough about the dark energy driving inflation to say that. If the force is constant for a given pair of particles at a constant distance, and the atoms are currently stable, that would seem to imply that the force from dark energy pushing the atoms apart will be the same as they are now.

However, as I said, I don't think we know enough about dark energy to say anything about its effects on the atomic scale either now or eons hence.

You're describing the Big Rip. It's now thought that the acceleration of expansion is not high enough for that to happen. Gravity is strong enough that the particles inside galaxy groups will stay causally connected indefinitely. Long enough into the future, whole groups will become disconnected from the rest of the universe, though.

Ah, I had never thought of it that way for some reason. Duh. Thanks.

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