What is expanding in the universe?

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Full disclosure: I’m high, but what exactly is expanding in the universe? Like I read something at some point that said that galaxies and cosmological bodies aren’t actually moving away from us faster than light, the space between them is just expanding. They made a distinction somehow but now, a long time after reading that, I’m sitting here wondering what it is that’s expanding… and wouldn’t whatever it is be expanding faster than light? I hope someone can help because I’m starting to spiral out.

In: Physics

4 Answers

Anonymous 0 Comments

Best example I know is the balloon example

Draw a bunch of dots 1 inch apart on a balloon. Now blow up the balloon. As you fill the balloon, the dots get further apart The dots didn’t move, but the space between them is now larger

Instead of the two dimensional surface of the balloon stretching and growing, it’s all of space stretching and growing. It’s not that the stars are moving away from eachother; just like the edits on the balloon the space between us is simply growing

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