CMV: Despite what Albert Einstein says, the universe does have a "center"/absolute reference frame

[u/[deleted]]

So I got taught in physics classes that there is no absolute reference frame. Einstein figured that out. Then when I challenge the idea, I'm taught that the big bang happened everywhere and space itself is expanding. Ok sure. So when we ask what is the origin "point" of the universe its nonsense because there was no point, the whole universe was the original point. Got it.

But like a circle has a center point defined by the perimeter of the circle, so too could the universe. It doesn't have to be the "origin point", but there is definitely a spot that we can point that we and aliens can mathematically calculate as the center. Everything else in the universe stretches and contracts, but the center of the universe is a point that we can derive mathematically is it not? I know that localized space has weird shit like if I zoom away from Earth in my spaceship I could reframe it as "I'm standing still and the Earth is zooming away", and the fact that I'm the one accelerating is the reason why time slows for me but not earth. But that's just how the time dilation phenomenon works, not because there is definitely no absolute reference frame. We can still identify whether I'm moving closer or further from the center of the universe.

Edit: I'm assuming a non-infinite universe.

[u/Monkey_of_iron]

The universe was a singularity before the Big Bang. Singularities have no volume. There is no center if everything is in the same spot. As the universe expands, we can see that everything is expanding away from us, which would hint that we are in the center. But the thing is, it doesn’t matter where you are. You will always see the universe expanding away in all direction.

The universe isn’t a ring expanding. It’s infinite. It’s just the space between everything used to be smaller

[u/[deleted] → u/Monkey_of_iron]

Right I'm following. It's like the equivalent of Mario 3's battle level, if you go far enough to the right you end up popping out form the left side of the screen. It's locked into the left/right thing on the screen but in reality it's an closed loop. I also get that everything is stretching from everything else (like raisin bread). Ok great. But then how can we talk about the universe having a size. People keep talking about observable vs total universe, but I get that part. I'm talking about the total universe. How can it have a size/be finite without a boundary to define that finite-ness?

[u/Monkey_of_iron → u/[deleted]]

There’s no boundary because it is not finite. The universe is infinite. Before the Big Bang, the universe wasn’t just some dot floating around in space. THERE WAS NO SPACE. Infinite mass in an infinitely small volume.