The Ultimate Spinning Universe: Does It End?

[PhanthomJay]

Ok, so the Earth spins around its axis, and around the sun; and the sun spins around the black hole at the center of the Milky Way galaxy; and that center spins around some other monster black hole at the galactic center of a cluster of galaxies, which, in turn spins about another monster monster black hole at the center of the center of the cluster of glaxies, etc. etc., and all this spinnning makes me dizzy. QUESTION: Ultimately, does the spinning end? Is there one mother of all black holes? It would seem that if not, then there must be an infinite number of black holes in an infinite universe.

 

[MeJennifer]

QUESTION: Ultimately, does the spinning end? Is there one mother of all black holes? It would seem that if not, then there must be an infinite number of black holes in an infinite universe.

General relativity theory does not exclude the possibility of a spinning universe. But I do not think we know if that is actually the case in our universe.

 

[PhanthomJay]

General relativity theory does not exclude the possibility of a spinning universe. But I do not think we know if that is actually the case in our universe.

Thanks. I see universes rotating about universes, and so forth, to infinity, but since this is just speculation, let's drop it right here. Thanks.

 

[derekmcd]

Ok, so the Earth spins around its axis, and around the sun; and the sun spins around the black hole at the center of the Milky Way galaxy; and that center spins around some other monster black hole at the galactic center of a cluster of galaxies, which, in turn spins about another monster monster black hole at the center of the center of the cluster of glaxies, etc. etc., and all this spinnning makes me dizzy. QUESTION: Ultimately, does the spinning end? Is there one mother of all black holes? It would seem that if not, then there must be an infinite number of black holes in an infinite universe.

I don't believe there is any evidence for the Milky Way, or any other galaxy in the local group, being influenced by another external, central, supermassive black hole.

What you are asking, if I'm not mistaken, is that the universe has a preferred direction and that the matter within the universe has a net angular momentum. Certainly, If there was a central "monster monster" black hole at the "center of the center", then that might indicate there is a direction and angular momentum.

I believe the current LambdaCDM model doesn't rely on either and actually precludes either direction or angular momentum.

If you are asking if the Universe, as a whole, spins... I would ask in relation to what does it spin and how could we recognize it?

 

[jonmtkisco]

A spinning structure can be truly symmetrical only in two of the three spatial dimensions. Specifically in the two dimensions of its equatorial plane of rotation (i.e., orthogonal to its rotation axis.)

I think a spinning observable universe (whether or not the entire universe is spinning) would be detectable due to the anisotropy of the matter distribution and the recession velocity biased in the general directions pointed by its rotation axis. Think of it as the Newtonian centrifugal and Coriolis pseudo-forces in action, distorting the otherwise symmetrical collapse action of gravity. Of course if the angular velocity of rotation is very slight, the effect might be too small to detect. Some rotational shear might also be detectable, with the most distant galaxies all appearing to move consistently in a retrograde direction relative to nearby galaxies, due to their differing orbital periods.

If the universe is expanding, then my guess is that the angular momentum of the spin would constitute a form of peculiar motion which would be diluted over time by the Hubble expansion, at the rate of 1/a (with a being the scale factor of the observable universe). If the universe were static, then it seems possible for the spin to be quite stable if it is already in virial equilibrium (although it seems impossible that enough time has elapsed since the big bang for particles which are too far apart to be in causal contact with each other to gravitationally synchronize their motions). In that case, over time the spin would be defeated only by the perturbative effects of gravity waves and collisions and near-collisions between massive objects, which nudge or toss them out of the symmetrical spin pattern, resulting in chaotic motion.

I note that since a rotating universe requires a unique axis of rotation, which could be thought of as the linear "center of the universe", it would violate some people's notion of a strong cosmological principle.

Jon

 

[PhanthomJay]

I don't believe there is any evidence for the Milky Way, or any other galaxy in the local group, being influenced by another external, central, supermassive black hole.

My assumption was that the Milky Way Galaxy, and other galaxies of the local group, are rotating as a whole, and perhaps with other clusters of galaxies, around some 'entity' or supermasive black hole at the center of the rotation. You are saying that this is an incorrect or unproven assumption?

 

[Chronos]

A spinning universe would be observationally detectable. No credible observational support for this conjecture has yet been detected.

 

[Blueprint]

My assumption was that the Milky Way Galaxy, and other galaxies of the local group, are rotating as a whole, and perhaps with other clusters of galaxies, around some 'entity' or supermasive black hole at the center of the rotation. You are saying that this is an incorrect or unproven assumption?

http://content.answers.com/main/content/wp/en-commons/2/2f/Local_Group.JPG

Yes I'd say that was incorrect. Take a look at a map of our local group, and note the massive expanses of millions and millions of light years of nothingness inbetween the galaxies. I guess you are assuming gravity would be the overriding force, but, correct me I'm wrong, the expansion of space has meant these galaxies are just too spread out for them to all be orbiting each other.

Thats not to say some clusters and galaxies that formed from nearby nebulas can and do gravitationally lock, merge together or orbit supermassive black holes.

 

[jonmtkisco]

There are large structures which are gravitationally bound and may be in virial equilibrium (that is, they have settled into a constant rotation rate). These are galaxy clusters. Rich galaxy clusters may contain up to thousands of galaxies within a fairly small radius. The majority of the mass in galaxy clusters does not come from the galaxies, it comes from a dense cloud of hot gas and dust (and of course is dominated dark matter) which is referred to as the intracluster medium.

Observationally it is obvious that our MW galaxy is not located in such a galaxy cluster. Our galaxy is paired with the Andromeda galaxy and a few miniature galaxies which collectively are called our Local Group. Its radius is not much less than that of a galaxy cluster, which illustrates how much difference there is in the density of our galactic neighborhood compared to those clusters.

Our Local Group in turn is considered to be part of a much larger collection of galaxies, galaxy groups, and galaxy clusters, called the Local Supercluster. However, recent observations indicate that superclusters are not gravitationally bound structures, in the sense that each supercluster is expanding, probably at an accelerating rate.

Jon

 

[Blueprint]

Good explanation Jon. I just read all the galaxies in our local group (but prob not local supercluster) display blueshift (approach... or rotation?), whereas (nearly) all the other observable galaxies/objects display redshift.

 

[jonmtkisco]

Hi Blueprint,
Yes, the overall blueshift of the Andromeda galaxy indicates that it is moving toward us at about 300 km/sec. Most of the dwarf galaxies in the Local Group are considered to be "companions" of MW or Andromeda, being gravitationally bound and in orbit around one or the other. The Triangulum galaxy, the 3rd largest galaxy in the group, is believed to be a companion of Andromeda.

If a galaxy is reasonably nearby and is large enough, and is situated mostly edgewise to us, we can detect that one edge is more redshifted (or blueshifted) relative to the other edge, which enables an estimate of the galaxy's rotation speed.

Jon

 

[Chronos]

Sounds like a theory in the making. Please elaborate the one you have in mind along with observational evidence.
.

 

[jonmtkisco]

Hi Chronos,
I assume your request is directed to PhantomJay, not me.

Jon

 

[George Jones]

If you are asking if the Universe, as a whole, spins... I would ask in relation to what does it spin and how could we recognize it?

Friedmann-Robertson-Walker universes don't have spin, but it is possible to have universes that have non-zero vorticity tensors. Godel came up with a spinning universe model more than fifty years ago. His model: has closed timelike curves; has no observational basis.

A few months ago, media http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/10/15/scistars115.xml" by the same group indicates that these reports were premature, and that there is no statistical evidence for a preferred sense of rotation.

 

[BoomBoom]

However, recent observations indicate that superclusters are not gravitationally bound structures, in the sense that each supercluster is expanding, probably at an accelerating rate.

Really?! This goes against everything I have heard or read...or was that just a poor choice of words? Did you mean receding from us?

Also, I have heard that our local group is migrating towards the local supercluster. If this is so, why would that light be redshifted?

If my assumptions are incorrect, please correct me. :)

 

[jonmtkisco]

Hi George,

Further statistical analysis[/URL] by the same group indicates that these reports were premature, and that there is no statistical evidence for a preferred sense of rotation.

It's an informative study about tabulating individual galaxy spins, but of course the authors do not suggest that a slight statistical imbalance of galaxy spins to clockwise or counterclockwise in one or two regions of space as viewed from Earth would have any connection to whether the cosmic matter field as a whole is spinning. Most likely if it occurred it would be attributable to local effects such as magnetic fields or gravitational collapse mechanics.

Jon

 

[robheus]

General relativity theory does not exclude the possibility of a spinning universe. But I do not think we know if that is actually the case in our universe.

A spinning of the universe as a whole would showup as an accelerated expansion.

 

[robheus]

A rotating universe is an exact solution to the Einstein equations.
See http://en.wikipedia.org/wiki/Gödel_metric

 

[PhanthomJay]

Sounds like a theory in the making. Please elaborate the one you have in mind along with observational evidence.
.

I don't have any evidence, I just 'feel' that since stars rotate about black holes at the center of galaxies, then (logically?) one might assume that galaxies rotate about black holes at centers of clusters of galaxies.
I do have another question: I believe I read somewhere that the distant galaxies are moving away from us, at an accelerating rate, due to spacetime expansion, but that the galaxies themselves are actually 'stationary' with respect to us, that is, their apparent recession speed from us, at or beyond the speed of light, is due entirely to spacetime expansion and not due to actual movement of those galaxies at some velocity with respect to space. Comment??

 

[MeJennifer]

A spinning of the universe as a whole would showup as an accelerated expansion.

Could you provide a source for your claim?

 

[Peter (IMC)]

I don't believe there is any evidence for the Milky Way, or any other galaxy in the local group, being influenced by another external, central, supermassive black hole.

What you are asking, if I'm not mistaken, is that the universe has a preferred direction and that the matter within the universe has a net angular momentum. Certainly, If there was a central "monster monster" black hole at the "center of the center", then that might indicate there is a direction and angular momentum.

I believe the current LambdaCDM model doesn't rely on either and actually precludes either direction or angular momentum.

If you are asking if the Universe, as a whole, spins... I would ask in relation to what does it spin and how could we recognize it?

If everything is spinning, wouldn't that mean there is some kind of centrifugal force that would make everything move away from each other? (Expanding space?) Since space doesn't have a center, you couldn't measure the direction of the centrifugal force, but it's effect would pretty much be in all directions?

I'm just guessing here. It's an interesting concept, all this spinning.

 

[robertm]

I don't have any evidence, I just 'feel' that since stars rotate about black holes at the center of galaxies, then (logically?) one might assume that galaxies rotate about black holes at centers of clusters of galaxies.
I do have another question: I believe I read somewhere that the distant galaxies are moving away from us, at an accelerating rate, due to spacetime expansion, but that the galaxies themselves are actually 'stationary' with respect to us, that is, their apparent recession speed from us, at or beyond the speed of light, is due entirely to spacetime expansion and not due to actual movement of those galaxies at some velocity with respect to space. Comment??

You're on the right track there PhanthomJay, try these: http://www.astro.princeton.edu/~aes/AST105/Readings/misconceptionsBigBang.pdf"
http://arxiv.org/PS_cache/astro-ph/pdf/0310/0310808v2.pdf"


As far as the gravitational rotation betwixt galaxies, it is certainly not from massive central black holes. Super massive black holes exists at the centre of galaxies their masses determined by the amount of material they have 'fed' upon in since their formations; and matter in a galactic system will orbit about a centre of mass very close to the central or grouping of central black hole/s. I am not quite sure on what scale galaxy clusters are no longer gravitationally bound, but in systems that are one must keep in mind that they are quite complex and will orbit on trajectories based upon the centre of masses between the complex groupings of multiple galactic systems. Sorry, no monster at the centre! ( naturally the larger galaxies will tend to be closer to the centre of mass of a given system)

One can not always rely upon deductive reasoning when dealing with scales in the millions of light years! Best stick to mathematics and observations! (well perhaps a little play is in order)