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CraigS
09-07-2011, 10:46 AM
The universe may have been born spinning, according to new findings on the symmetry of the cosmos (http://www.physorg.com/news/2011-07-universe-born-symmetry-cosmos.html)

… yikes !! :eyepop:

Cheers

sjastro
09-07-2011, 11:34 AM
Interesting.

Your mate Godel of "mathematical proof is incomplete" fame came up with a metric for a rotating Universe which is a solution to Einstein's field equations.

http://en.wikipedia.org/wiki/G%C3%B6del_metric#Cosmological_Inte rpretation

Regards

Steven

CraigS
09-07-2011, 11:41 AM
.. but with no Hubble expansion ! :confused2:

Cheers

sjastro
09-07-2011, 12:08 PM
A rotating Universe where Hubble expansion is replaced by centrifugal forces?
I can see Cosmologists jumping all over this idle thought.:lol:

One question, since galaxies do not all lie in the same orbital plane how do they explain the rotation for galaxies where the plane of the galaxy is "parallel" to the "rotational axis" of the Universe?

Regards

Steven

renormalised
09-07-2011, 02:19 PM
Here's the journal article, guys...

renormalised
09-07-2011, 03:15 PM
You can say that again!!!. Not only does it mean there has to be a preferential frame of reference (the frame of rotation...i.e. the rotational axis of the universe), it also means that there must be a constant of centrifugal force which mirrors the Hubble constant. It would also mean that any one galaxy could be shown to have an unique set of positional parameters w.r.t. every other galaxy because of the defined rotational axis. What it would mean is that it could be possible to observe the axis of rotation in space, by looking at the ways the galaxies behaved.

However, all that could be discarded if you look at the universe as being a spherical 4D surface of a higher dimensional object, where the poles of rotation lie outside the surface of the shell, as well as its rotational axis. The rotational axis would essentially exist in the higher dimensional state. The surface of the shell could keep expanding in the same manner as it has always been theorised, only that the galaxies which lie within that shell (the observable universe) could exhibit this handedness asymmetry which might be due to some sort of "universal coriolis effect" on the contents of the shell due to the rotation. This could also explain the anomalous flow in the superclusters of galaxies that they have seen out near the Hubble Wall.

A galaxy whose plane was parallel to the rotational axis of the Universe could exhibit an "ambidextrous" nature, when it comes to its own axis of rotation, depending on the relative positions of the galaxy and any observer of that galaxy. A galaxy might exhibit counterclockwise rotation on one side of the rotational axis and clockwise on the other, due to its own rotational axis being perpendicular to the overall universal rotation. It could also mean weird effects would be exhibited by the spectrum of any such object, depending on the geometrical relationship between the universal rotational axis and its own position in w.r.t. that axis at any given time of observation.

Though, it could all be moot if you consider that any "handedness" in the rotation of galaxies maybe nothing more than a "mirage" of observation. That is, a galaxy or a group of galaxies which seem to exhibit a sinistral rotational handedness (left handed) can just as easily be dextral if you observe those galaxies from the diametrically opposite direction. That being the case, the overall handed condition of the galaxies within the Universe maybe random, no matter which direction you observe from.

renormalised
09-07-2011, 03:25 PM
The problem with keeping universal expansion and attributing galactic handedness to universal rotation is that even with the rotation and the poles of rotation lying outside what is observable, if the "universal coriolis effect" held, at the "putative position" of the polar areas, there'd be an overabundance of one handedness type over the other at that position (the coriolis force being at the max in those areas). Handedness, as I've said previously, mightn't be a good criteria for defining any geometrical aspect to the universe or to its constituents.

renormalised
09-07-2011, 03:44 PM
Just had a thought....all things being equal and true for that study, you should be able to tell where you are w.r.t. the overall shape of the Universe from the handedness exhibited by the galaxies in your section of the Universe. Although you wouldn't be able to see the other sections of "Observable Universes" in the overall structure, you could theoretically define where you were by the amount of handedness asymmetry the galaxies exhibited in your own section. The further away from the universal "equatorial region" the greater the asymmetry between left and right handed galactic rotations. If this is correct, it may mean that a 7% asymmetry between left and right handed galaxies for our section puts us somewhere rather close to the "equator" of the overall Universe.

This is all depends on the Universe being a spherical object and that it spins.

renormalised
09-07-2011, 03:49 PM
My brain is going to melt in a minute!!!. I haven't slept in over 32 hours and I've been out at the local GH with an illness (a bad allergy to an injection and an infection that's related), so if I don't make sense or I've missed something obvious, I have an excuse:):P

CraigS
09-07-2011, 03:56 PM
I think I agree !

The expectation that all galaxies should have the same handedness is really what's in question here. And if they do display some bias, does that really mean anything in the overall scheme of something as big and complex as the universe ? Does it really mean there is a preferred frame of reference ?

As an example of nature not measuring up to our 'expectations': take retrograde orbital motions of moons (Like Triton). Some of the exo-planets also have retrograde orbits as well. Was there ever an expectation that this shouldn't occur ? (I think 'yes').

Is the 'cosmic accident', (which is something like one in a million), sufficient to draw an inference that this is a 'non-accident', or is it just a matter of sample size bias ?

I haven't read their paper yet … thanks for that, Carl.

Good to see the Cosmological Principle being queried though … (I don't think this'll ever stop .. which is a good thing).

Cheers

CraigS
09-07-2011, 03:59 PM
I wish I had a similar excuse … unfortunately my excuse isn't as good as that one (sounds nasty) …

Cheers

renormalised
09-07-2011, 04:04 PM
It is...it's sore and itchy at the same time and my left arm is swollen. I have no elbow at present and my arm goes numb quite regularly. I'm on clindamycin (can't take penecillin...I'm allergic to it) which is one of the strongest antibiotics you can get and the doc had to ring Canberra for permission to prescribe it. With being dog tired and unable to sleep, plus not feeling all that great anyway, I'm not running on all cylinders!!!:)

CraigS
09-07-2011, 04:11 PM
Take it easy, dude.

.. You'll keep for another time … :evil:
:P :)

CraigS
12-07-2011, 04:38 PM
Interesting … this physics professor Michael Longo, has been duelling with the Galaxy Zoo team for some time about this. They published a paper in 2008 (http://arxiv.org/pdf/0803.3247v4) and found no such asymmetry. They cite a "human visual perception bias in the raw data". (Their data was classified by members of the public). The data set in the Galaxy Zoo study of 2008, included a sample of about 37,000 spiral galaxies from the SDSS survey.

Longo's present sample uses only 15,158 spiral galaxies with redshifts <0.085 from the Sloan Digital Sky Survey. He says:

His current paper is here. (http://arxiv.org/ftp/arxiv/papers/1104/1104.2815.pdf)

Somehow, I don't think we've heard the last of this duel.

However, of interest is that the widespread use of the public to gather and classify data, requires extra careful handling in the analysis .. something we're likely to have to look out for with these huge sky-wide survey projects.

The next chapter in this one will be interesting to see unfold (as 'the Zoo' responds to Longo's latest results).

Cheers

renormalised
12-07-2011, 05:07 PM
The problems with these surveys is that they are too narrow in their focus to really be of any use, except on the scales they observe them at. If you're going to resolve any question about the Universe having some sort of rotational symmetry and a bias in handedness of the rotation of galaxies due to this, you'll need much larger and more widespread surveys to be carried out. If the rotational asymmetry of the galaxies is present now, it should be present in the past and even more so. The reason being is the conservation of angular momentum. The early universe must have been spinning faster than now, and if the present angular rotational rate affects the galaxies handedness now, how much more would it have affected it back then. The asymmetry would've been more pronounced. So, we really have to look back to at least z=1 (8Gly) and possibly as far back as at least z=2 or 3, to get a good idea of what's going on. That means sampling at the very least 5-10 million galaxies. Mind you, these galaxies should ideally be observed from every direction, so we get no bias in the direction of the observations being made.

Only going back to <0.085 (<1.34Gly) is virtually looking in our backyard for evidence of something that's happening 2 blocks down the street. At z=0.3 (3.5Gly), it marginally better. At least you're looking at the closest backyard in one of those blocks.

CraigS
12-07-2011, 05:14 PM
Yep I suppose so … but as Longo said, the higher z galaxies are fainter and its harder to pick the handedness because of that.

.. also ...

… why is this .. ie: what are your assumptions underpinning this ?

Cheers
PS: The Galaxy Zooers looked at 37 K galaxies ! That's a pretty reasonable sample size.

renormalised
12-07-2011, 06:22 PM
That's why you need a survey to be done by a large space telescope (maybe the JWST or a derivative thereof).

Why is this??.....I answered that question in my previous post. Conservation of Angular Momentum....any object, no matter what it is, if it's undergoing rotation, it must therefore also have angular momentum. If you take the present universe to be spinning at X and with an angular momentum of Y, since that present angular momentum is large due to the size of the present universe (radius=Z), if you decrease the radius Z by a factor of 2 and therefore decrease the value Y correspondingly, in order to conserve the angular momentum for that smaller universe, you must spin it up faster, so X becomes larger. If, as they say, the rotation of the Universe is affecting the handedness of the rotation of the galaxies such that there's an asymmetry to that rotation, if you increase the rotational velocity to conserve the overall angular momentum, it would mean that in any given volume of the universe, there would be more galaxies showing that asymmetry because the volume of space occupied by galaxies in the smaller universe is, of course, smaller and there are more galaxies crammed into that space due to that reduction in size. It may have also meant that the actual % of galaxies showing an asymmetry was greater, as the faster rotation imposed itself upon the formation of those galaxies. Although, there may have been a cutoff point where the amount of rotation stopped affecting the rotational symmetry of the galaxies to the extent that most of the galaxies after this were of the typical handedness seen. The original "kacky handed" galaxies would still be influenced by the rotation, though, as they would appear to congregate in the flow in whatever direction the universe was still rotating.

That's why you need much larger sample sizes than the ones either study chose. They're really too small to actually calculate what the real % of handedness is and whether there is a predominant direction for "kacky handed" galaxies showing a rotation of the universe. What they're both doing is giving only a very rough approximate (either 0% or X%). However, you also have to take into account what the Zoo team said about observational bias.

avandonk
12-07-2011, 07:38 PM
It is very simple as each galaxie in their youth got pissed and started
spinning!

Realistically the inherent spin is due to quantum fluctuations. This is the standard answer when we do not have a clue!

Bert

CraigS
12-07-2011, 07:54 PM
Hmm .. its almost impossible to have a conversation about this without some clarity in the model underpinning it all. The assumptions are critical. For example, if the model is a Godel solution to Einstein's field equations, then there would be no expansion, so I don't know what to make of an increasing z radius over time :confused2:

Cheers

renormalised
13-07-2011, 01:18 AM
Probably closer to the truth than anything else....except....:):)

And that's more than likely even closer:):)

renormalised
13-07-2011, 01:23 AM
Standard BB cosmological model (FLRW)...so z (radius, in this case) increases with time.

The only way to invoke a Godel solution is to take the premise that the BB is wrong...but what do all the observations tell us. Unless, of course, we're also misinterpreting those observations as well.