• CrayonRosary@lemmy.world
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    15 days ago

    Isn’t the universe a sufficiently large size? Why is it expanding then? What constitutes an “object”?

    • PoastRotato@lemmy.world
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      15 days ago

      Most of the universe is empty space, and that’s what’s expanding. Empty space doesn’t have any gravitational pull

        • PoastRotato@lemmy.world
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          14 days ago

          Yes, but nuclear forces are strong enough to keep the space within from expanding and hold the objects together. It’s in the vast swathes of emptiness between galaxies that we typically see the exansion of space because gravity is too weak there to keep things together.