Rotating Universe: Instant Axis Rotation Proven!

[thetexan]

Rotating relative to what?

 

[RichyRich]

Thankyou very much Imax. A rotating universe is clearly not such a remote idea amongst physicists. My thoughts still linger to a rotation that is substantially different from rotations that occur WITHIN the universe. Am I correct in thinking phyicists believe 'we' should be bathed in magnetic monopoles, based on theory. The 'favourite' answer to this is the universe expanded to such a size these monopoles have been diluted out. We do not know what fraction of the universe we are sampling-observable to actual size of universe. Therefore, absence of evidence is not is not evidence of absence in monopoles or, I would suggest, in dynamical effects of universal rotation. So one of bcrowells earlier responses is invalid.
thetexan, I believe the universe rotates about/in what we would call another dimension. I am not alone in thinking there are other dimensions. Many physicists believe theory points in that direction. If there is something other than our universe, would anyone really expect 'us' to be static in relation to it?! bcrowell mentioned, when he was confident of an answer!, that GR says rotation can occur without reference to anything else, so that also could be an answer. bcrowell, however, only answered certain points, based on my attitude! I would have thought a more reasoned response to my 'attitude' would have been no response, not selective responses!
I would like to invite responses to the following thought. To me, it may be relevant to this thread and possibly to quantum theory. I really don't know, so would just like some comments about it in general...
Say you had a CD. This CD was a uniform colour, save for a blue dot at its outer edge. You are looking down onto the CD's flat surface whist it spins at an infinite speed. You put your finger on the outer edge to stop the CD rotating. Would you expect to stop the CD with your finger on the blue dot? What if the blue dot were actually suspended in a medium, say water, rotating in the same way. Wherever on the 'edge' of this water you put your finger in, would the blue dot be there? None of this is to make any point as such, just would like to see any comments. Thanks.

 

[bcrowell]

Rotating relative to what?

Rotation in GR is not relative, it's absolute. For example, if you're inside a sealed laboratory, you can watch the behavior of a gyroscope and determine whether the lab is rotating. This is one of the ways in which GR is non-Machian.

 

[RichyRich]

thetexan GR says rotation doesn't recquire extra dimensions, but doesn't rule them out.

 

[Imax]

The math could work out easier in 5D?

 

[Imax]

Baby steps. Instead of looking at a rotating universe, look at another question. Why do galaxies exist? Current cosmological models need Dark Matter and Dark Energy to explain why galaxies can form and don’t fall apart. Galaxies rotate and so could our Universe.

 

[bcrowell]

Baby steps. Instead of looking at a rotating universe, look at another question. Why do galaxies exist? Current cosmological models need Dark Matter and Dark Energy to explain why galaxies can form and don’t fall apart.

You don't need dark matter to explain why galaxies can form. You only need it to explain why they have the rotation curves they do. In a universe without dark matter, galaxies would still form, but they would have different sizes and rotation curves.

Dark *energy* has nothing to do with galactic structure.

Galaxies rotate and so could our Universe.

You haven't given any logical connection between your previous statements and this one. In any case, GR establishes that rotating cosmologies are possible, and observations set an upper limit on the rotation. See the references given in #13.

 

[Imax]

You don't need dark matter to explain why galaxies can form. You only need it to explain why they have the rotation curves they do. In a universe without dark matter, galaxies would still form, but they would have different sizes and rotation curves.

You need Dark Matter to explain why observed data does not fit with current theory. Without Dark Matter, galaxies could have different size and rotation (i.e. spin).

 

[bcrowell]

You need Dark Matter to explain why observed data does not fit with current theory. Without Dark Matter, galaxies could have different size and rotation (i.e. spin).

Agreed.

 

[RichyRich]

Whilst any observations are worthwhile, in this case they are useless. Would any dynammical effects observed from rotation prove the universe is rotating-no. It may be that the observable universe has some movement/rotation within the universe as a whole. Observation is irrelevant unless we know scale. The question was rotation of the whole universe, not observable universe. Another stumbling block for mr crowell to avoid.

 

[Imax]

So Dark Matter could cause the Universe to rotate?

 

[bcrowell]

So Dark Matter could cause the Universe to rotate?

Huh? Why do you say that?

 

[Imax]

Pulling your leg :)