this post was submitted on 13 Mar 2025
775 points (98.6% liked)

Memes

48499 readers
4366 users here now

Rules:

  1. Be civil and nice.
  2. Try not to excessively repost, as a rule of thumb, wait at least 2 months to do it if you have to.

founded 5 years ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] surph_ninja@lemmy.world 15 points 1 day ago (3 children)

If space is always expanding, I’d really like to know if a time traveler would experience issues existing in a universe where the space between atoms is different from the one they left.

[–] MonkderVierte@lemmy.ml 3 points 1 day ago

They are not, that would require changes in the strong force.

[–] BrainInABox@lemmy.ml 3 points 1 day ago

They wouldn't; the expansion of space isn't strong enough to change the distance between atoms; the force holding them together overcomes it.

[–] HurlingDurling@lemm.ee 8 points 1 day ago (2 children)

I was under the impression that gravity was a constant force keeping the atoms closer together

[–] stebo02@lemmy.dbzer0.com 11 points 1 day ago (1 children)

More importantly it's the electromagnetic force that keeps atoms together. Gravity only keeps planets and stars together and also solar systems and galaxies, but in ordinary objects it's totally negligible.

[–] Klear@sh.itjust.works 3 points 1 day ago

"Weaker than Weak".

[–] surph_ninja@lemmy.world 3 points 1 day ago (2 children)

Space itself is constantly expanding. Theories of the Big Rip predict the space between atomic particles could become vast enough to rip them apart.

[–] BrainInABox@lemmy.ml 2 points 1 day ago

The big rip scenario happens in the case where the rate of space expansion is increasing. It's possible, but we haven't seen any evidence of it yet, so far the rate appears constant, which means a heat death scenario.

[–] abraker95@lemmy.world 4 points 1 day ago* (last edited 1 day ago)

The big rip concept comes into play when the expansion rate starts to become faster than the forces holding molecules and atoms together. As far as current cosmic expansion goes, it only applies to space between galaxies. The current expansion rate is so weak it's not enough to overcome forces that hold galaxies together.