Wouldn't the center be the Big Bang and the 3D Universe at the current time (if Relativity lets me write about a current time) be the 3D surface of the 4D sphere (or spheroid) that the Big Bang is creating by keeping to expand?
Which would undercut practically all of modern physics. Really fundamental conservation laws like momentum and energy rely on the universe being equal in all directions. If it has a central axis, that does not hold.
So if that holds, it's potentially a major pointer to the very origins of the universe itself. But it's also one of those extraordinary claims that require extraordinary proof. I strongly doubt that this will stand up to scrutiny -- though I'll certainly be pleased if it turns out be true, because that will be a major advance in our understanding.
If everything started from a singularity that had a axiomatically uniform rotation, you might not be able to assess the center "axis" based from inside spacetime itself
This seems to be a variation of Mach's principle, which is one of the closest things to philosophy in physics!
To say that the universe rotates usually implies that it rotates with respect to something external. If we limit ourselves to the visible universe, this would mean that mass outside our light cones can actually influence us, by means of building the frame of reference that allows us to say that the universe rotates!
You don't need any external reference points to know that you're rotating. You could detect it by the apparent centrifugal force: objects in your own frame of reference don't move in straight lines.
It would imply that there exist privileged reference points within the universe, and that would be a major change to physics. I can't predict all of the consequences of that, and they might include some kind of external frame of reference. But that doesn't necessarily follow.
There is. The center of the observable universe is earth. Every alien civilization will see themselves at the center of thier observable universe. And each will observe the same rotation in faraway objects. Relativity makes things strange.
If you have two stars orbiting each other, they orbit a centre of gravity and they will probably both be rotating in the same direction as their orbits.
Is that a meaningful centre for anything else though?
pmontra|10 months ago
eggn00dles|10 months ago
jfengel|10 months ago
Which would undercut practically all of modern physics. Really fundamental conservation laws like momentum and energy rely on the universe being equal in all directions. If it has a central axis, that does not hold.
So if that holds, it's potentially a major pointer to the very origins of the universe itself. But it's also one of those extraordinary claims that require extraordinary proof. I strongly doubt that this will stand up to scrutiny -- though I'll certainly be pleased if it turns out be true, because that will be a major advance in our understanding.
altcognito|10 months ago
tatjam|10 months ago
To say that the universe rotates usually implies that it rotates with respect to something external. If we limit ourselves to the visible universe, this would mean that mass outside our light cones can actually influence us, by means of building the frame of reference that allows us to say that the universe rotates!
jfengel|10 months ago
It would imply that there exist privileged reference points within the universe, and that would be a major change to physics. I can't predict all of the consequences of that, and they might include some kind of external frame of reference. But that doesn't necessarily follow.
sandworm101|10 months ago
olddustytrail|10 months ago
If you have two stars orbiting each other, they orbit a centre of gravity and they will probably both be rotating in the same direction as their orbits.
Is that a meaningful centre for anything else though?
layer8|10 months ago
irrational|10 months ago
gitaarik|10 months ago
layer8|10 months ago