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A Dr. Serkan Zorba has a paper on arxiv in which he considers, what if the universe is actually slowly rotating? This gives rise to centrifugal and Coriolis forces on a galactic scale that seem to perfectly explain the effects of dark energy and dark matter. Not only that, but it explains a few other observations in cosmology.

But I haven't been able to find anyone else commenting on his model, and it's been several years now. Is there something wrong with it that allows us to dismiss it out of hand? Or do other cosmologists just not care?

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  • $\begingroup$ youtube.com/watch?v=GfesXDG848c $\endgroup$ – シャシュワト Oct 12 '18 at 21:46
  • $\begingroup$ This is a video of his. He explains what he did in the paper and says that his paper was rejected somewhere giving a reason that his "model concludes that the universe is anisotropic but the universe, as we know, is isotropic". Maybe this is the reason people ignore or don't talk much about his paper. Anyway, the table of data is really close to the data predicted by the current model which I find to be fascinating. $\endgroup$ – シャシュワト Oct 12 '18 at 21:48
  • $\begingroup$ @シャシュワト Thanks! It bugs me that it was rejected simply for that reason because he gives a falsifying test for the model. $\endgroup$ – HiddenBabel Oct 12 '18 at 23:09
  • $\begingroup$ I am no expert but the Hubble's constant and angular velocity do have the same units (that is the reason when multiplied by time $(t)$ they then can be exponentiated as $e^{\omega t}$ and $e^{H t}$ as $H t$ and $\omega t$ are dimensionless). Radians are dimensionless units. Are there no other noticeable flaws? $\endgroup$ – シャシュワト Oct 12 '18 at 23:10
  • $\begingroup$ 1.bp.blogspot.com/-RZE4TVESbDQ/VzY4bVAN46I/AAAAAAAABFg/… $\endgroup$ – シャシュワト Oct 12 '18 at 23:20
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This doesn't seem to have been presented or published anywhere other than as a somewhat casual/informal document on the arXiv, which probably helps explain why it's been ignored.

Well, that and the fact that it's ignorant of all the relevant research and is very, very wrong.

Since I'm not really a GR person, I'll pass over the first ("explains dark energy") part, though I suspect it's got serious problems.

The second part of the paper attempts to explain "dark matter" effects -- i.e., the rotation curves of galaxies (he doesn't seem aware of the role postulated dark matter plays in explaining galaxy group and cluster dynamics, or the overall energy density of the universe) -- with the Coriolis force. This requires that disk galaxies be oriented so that their angular momentum vectors are parallel to the axis of universal rotation. But for galaxies oriented perpendicular to that direction, the Coriolis effect vanishes. Since real galaxies are randomly oriented, this effect would have been obvious back in the 1970s, when people like Vera Rubin were measuring outer rotation curves of galaxies and finding evidence for dark matter. All disk galaxies show roughly the same dark matter effects, regardless of their orientation.

Put another way, in order for this model to explain dark matter, all disk galaxies would have to have the same orientation in 3D space. So all the galaxies we observe would have the same position angle on the sky, with all galaxies near the Galactic plane seen edge-on and all galaxies near the Galactic poles seen face-on. Needless to say, this is not our universe.

The real killer is that the whole model requires the universe to be uniformly rotating with an angular speed approximately equal to the Hubble constant $H_{0}$. But a rotating universe would produce distortions in the cosmic background radiation, as pointed out by Stephen Hawking back in 1969. This was the first in a series of papers attempting to measure, or put upper limits, on the vorticity of the universe. This is usually parameterized as the ratio of the vorticity $\omega$ to the Hubble constant: $\omega / H_{0}$ (note that Zorba uses "$\omega$" for the angular speed). Since the vorticity of a uniformly rotating system is just twice its angular speed, Zorba's model is $\omega/H_{0} \approx 2$. Hawking was able to derive crude upper limits of $\omega / H_{0} < 10^{-3}$, meaning that Zorba's preferred value would be about a thousand times too large. Barrow et al. (1985), using updated data and a more detailed analysis, found an upper limit of $\omega / H_{0} < 2 \times 10^{-5}$.

Studies since then have pushed the upper limit further down. The most recent attempt is probably this paper in Physical Review Letters by Saadeh et al. (2016), which uses both temperature and polarization data from the Planck satellite and finds $\omega / H_{0} < 4.7 \times 10^{-11}$.

In other words, if the universe is rotating, it's doing so about a trillion times more slowly than what Zorba's model assumes.

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  • $\begingroup$ do you have a link for a measured "Since real galaxies are randomly oriented" my impression is that the "axis of evil" says that they are not? also your quotes about the equality of the omega with the hubble constant talk of a rotating universe alone in the cosmos, whereas the spin model has it as an item in a bigger set, rotating outside the in an overuniverse, as far as I understand. $\endgroup$ – anna v Oct 14 '18 at 11:22
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    $\begingroup$ The "axis of evil" is a supposed (and disputed) anisotropy in the cosmic microwave background, allegedly aligned with the plane of the Solar System; it has nothing to do with the alignments of galaxies. The uniformity of orientation required by Zorba's model means, for example, that every galaxy seen in projection near the plane of the Milky Way would be edge-on, and that every galaxy near the north or south Galactic poles would be face-on. This is basic astronomy, something that would have been obvious to 19th Century observers looking at "spiral nebulae". $\endgroup$ – Peter Erwin Oct 14 '18 at 13:13
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    $\begingroup$ "the spin model has it as an item in a bigger set, rotating outside the in an overuniverse" -- the supposed "bigger set" plays no role in Zorba's model; he's assuming the entire observable universe is well inside his (arbitrary, unmotivated) "disk-shaped model", and his GR discussion assumes a uniformly rotating universe, full stop. $\endgroup$ – Peter Erwin Oct 14 '18 at 13:28
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    $\begingroup$ well, as I read it, that is the whole point, otherwise the hubble constant and the limits of rotation of the universe of the big bang model exclude it. IMO, he assumes our universe is a small part of a rotating outside multiverse or some such. Anyway, we know where we disgagree. $\endgroup$ – anna v Oct 14 '18 at 13:31
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    $\begingroup$ @HiddenBabel -- "Zorba does consider the fact that galaxies can have different orientations" -- no, he does not. He does consider exactly what you say he doesn't, and even touts this as a specific observational prediction -- and then he alludes to "different orientations" as one of the things making individual observations more difficult, and decides to just compute the "average", which uses the Coriolis equation for the perfectly parallel model he started with, which assumes all galaxies have the same ideal orientation. $\endgroup$ – Peter Erwin Oct 15 '18 at 7:00
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I looked through the paper ( not the formulae, as I cannot catch errors if they are there).

Is there something wrong with it that allows us to dismiss it out of hand? Or do other cosmologists just not care?

It is unfortunate that the paper has not been published if there are no algebraic/computational errors because somebody would have come out with a reasonable defense of the Big Bang standard model against this new proposition. I hope somebody good in cosmological models reads it here and enlightens us. To me it sounds as an intriguing model which does not require modifications of General relativity and seems to be able to model existing observations, including giving a reason for the axis of evil .

Actually this last, if I understand it correctly, gives a prediction also, that on average all planetary systems should on average be in the same plane of rotation as our sun system.

One has to accept that there are fashions in physics, and as physicists are also people, sociological behaviors dominate too. The fashion now is the Big Bang, and particles for dark matter. In particle physics, having lived through the emergence of QCD over Feynman's parton model, and the difficulties of getting it universally accepted, I am not surprised that this is not discussed even at the level of Mond.

I hope, if there is nothing computationally wrong or falsified directly by existing observations, this will get more attention.

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    $\begingroup$ Papers are not ignored just because of "fashion". There are tons of papers about dark matter every day that don't follow the WIMP paradigm, the ones that are ignored are ignored because they're bad. In this case, this paper's model makes several blatantly wrong predictions. (It only works for things rotating in one plane, and rotation effects of this magnitude have been ruled out for decades.) $\endgroup$ – knzhou Oct 14 '18 at 10:04
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    $\begingroup$ @HiddenBabel I get what you're going for, but if you focus on looking at "alternative" models that aren't getting attention, you're going to get stuck in a morass of individuals' pet theories that claim to explain everything and actually explain nothing. This guy even claims his model explains inflation and quantum gravity in addition to everything else. There are literally thousands of such people, greatly outnumbering the people who actually know what they're doing. They're a dime a dozen. $\endgroup$ – knzhou Oct 14 '18 at 10:07
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    $\begingroup$ In the beginning he states "The rotation of the spacetime of our universe implies that there is extraneous physics, i.e., our universe is not a closed system, and that there is a larger universe or cosmically parallel universe.And the implied cosmic axis of the model must have had axial precession (see Fig. 1). The resulting overall u niverse would be disk - shaped, but i f the size of our observable un iverse is only a fraction of the overall, (s) $\endgroup$ – anna v Oct 14 '18 at 14:35
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    $\begingroup$ The axis is outside our obsrvable universe. fig 1 $\endgroup$ – anna v Oct 14 '18 at 14:38
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    $\begingroup$ @annav -- The stuff about "extraneous physics" and "cosmically parallel universe" (and that the universe is "disk-shaped" and "must have had axial precession") is meaningless verbiage. Nothing in his mathematical derivations depends on any of that. $\endgroup$ – Peter Erwin Oct 15 '18 at 7:03

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