• @[email protected]
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    153 days ago

    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.

    • @[email protected]
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      83 days ago

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

      • stebo
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        113 days ago

        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.

      • @[email protected]
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        33 days ago

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

        • @[email protected]
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          3 days 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.

        • @[email protected]
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          23 days 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.

    • @[email protected]
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      33 days 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.