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submitted 2 days ago by [email protected] to c/[email protected]

It's easy to think about the creation of the Universe like exploding fireworks: Start with a big bang, and then all the galaxies in the Universe fly out in all directions from some central point.

But that analogy isn't correct. Not only does it falsely imply that the expansion of the Universe started from a single spot, which it didn't, but it also suggests that the galaxies are the things that are moving, which isn't entirely accurate.

It's not so much the galaxies that are moving away from each other – it's the space between galaxies, the fabric of the Universe itself, that's ever-expanding as time goes on. In other words, it's not really the galaxies themselves that are moving through the Universe; it's more that the Universe itself is carrying them farther away as it expands.

A common analogy is to imagine sticking some dots on the surface of a balloon. As you blow air into the balloon, it expands. Because the dots are stuck on the surface of the balloon, they get farther apart.

Though they may appear to move, the dots actually stay exactly where you put them, and the distance between them gets bigger simply by virtue of the balloon's expansion. ... The thing we think of as the "center" of the balloon is a point somewhere in its interior, in the air-filled space beneath the surface.

But in this analogy, the Universe is more like the latex surface of the balloon. The balloon's air-filled interior has no counterpart in our Universe, so we can't use that part of the analogy – only the surface matters.

So asking, "Where's the center of the Universe?" is somewhat like asking, "Where's the center of the balloon's surface?" There simply isn't one. You could travel along the surface of the balloon in any direction, for as long as you like, and you'd never once reach a place you could call its center because you'd never actually leave the surface.

In the same way, you could travel in any direction in the Universe and would never find its center because, much like the surface of the balloon, it simply doesn't have one.

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[-] [email protected] -5 points 2 days ago

those guys are so lost in semantics

[-] [email protected] 3 points 1 day ago

Imagine an infinitely large box with nothing in it. Where is the center? There isn't one.

Imagine that box suddenly fills with pieces of stuff, more or less evenly distributed. Still no center.

Imagine the box starts getting bigger, but the amount of stuff stays the same and the distance between stuff quickly increases even though the stuff isn't moving that fast. Where's the center of the infinitely large box?

[-] [email protected] 0 points 1 day ago

i think you replied to the wrong comment.

this post was submitted on 12 Jun 2025
35 points (94.9% liked)

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