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In 2008, the European Southern Observatory reported, upon the end of a 16-year study described here http://www.eso.org/public/usa/news/eso0846/, that the 28 stars nearest the very large black hole in Sagittarius A included 22 in varied orbits compared to a "swarm of bees", and six (all slightly farther from the BH) in a disc of very fast orbits. As the stars were "too young" to have migrated far, and as the tidal forces in black holes had apparently been felt to leave star formation in that region unlikely, further research was planned. I'm asking whether there might have been any results, given the torsion-based cosmology which pairs black holes with white ones and is most concisely described at arXiv.org > https://arxiv.org/abs/1510.08834.

The spin of smaller celestial bodies may affect the spin of the larger systems of which they're a part to an extremely great extent, according to a version of inflationary cosmology developed by physicist Nikodem Poplawski since 2009. The simplest statement of his cosmology is at https://arxiv.org/pdf/1007.0587.pdf, but, in spite of its title as an "alternative" to cosmological inflation, it actually describes a version of that theory, as pointed out in the Wikipedia article "Inflation": Poplawski's version uses an extension of Einstein's General Relativity that's usually referred to as the Einstein-Cartan-Sciama-Kibble (ECSK) theory of gravity, and was developed, partly in consultation between Einstein and the French mathematician Cartan, to incorporate particulate spin (the rotation of subatomic particles) into relativity, since GR had been formulated several years before such spin was discovered.

Partly because ECSK made an assumption that fermions (loosely describable as "matter particles") have a spatial extent (tiny, but about 37 times the Planck length) that's incompatible with a renormalization technique useful in quantum mechanics (which generally requires all subatomic particles to be pointlike), and perhaps partly because its application to cosmology allows a universe that's eternal to the past and to the future rather than one that's eternal only to the future, the ECSK theory has not been widely utilized in cosmology until recently, when physicists exasperated with the failure to discover any specialized subatomic particle that would cause inflation began turning to it. As you can see on p.7 in the piece I've linked you to, Poplawski's torsion-based cosmology may be falsified if there's no evidence for any prevalent direction of rotation, whereas inflationary cosmology that's based on a field of hypothesized "inflaton" particles cannot be falsified at all, leading to many recent objections to it by theoreticians.

I'd also like to know (if possible) whether the direction of the orbits of the stars concerned is the same as the direction of rotation of the super-massive BH itself, assuming that the latter was not inferred from the former: This would help me to assess the plausibility of this BH cosmology, as one of its leading proponents (Nikodem Poplawski) feels the arrow of time to derive from the direction of matter's passage across the event horizons of BHs, and has also felt the torsion-based theory to be falsifiable by the lack of a prevalent direction of rotation in the universe. (These are details to me, but might appear in whatever conversations or observations might contain the answer to my question.)

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  • $\begingroup$ Is there an actual link for: 'arXiv.org > astro-ph > arXiv:1510.08834'? And where does a "white hole" theory relate to your second paragraph? $\endgroup$
    – user10106
    Commented Mar 12, 2018 at 16:38
  • $\begingroup$ It's worth noting that the article you link to is ten years old, and likely not representative of the current state of knowledge of the area. $\endgroup$
    – HDE 226868 ♦
    Commented Mar 12, 2018 at 16:46
  • $\begingroup$ @ Kozaky-here's the link-"arXiv:1510.08834'"-you might have to copy it and paste it. $\endgroup$
    – Edouard
    Commented Mar 13, 2018 at 17:26
  • $\begingroup$ @ HDE 226868-remember that the original study, upon which further research was needed, had lasted 16 years, not just 10. (16 years, incidentally, was all the time the fastest of the 6 stars in the disc of orbits had taken to orbit the galactic center!) $\endgroup$
    – Edouard
    Commented Mar 13, 2018 at 17:35
  • $\begingroup$ @ Kozaky-there have been problems with what's called "link rot", so you may need to Google search the paper by its title, which is "Non-parametric reconstruction of an inflaton potential". The reason why I threw in the 2nd paragraph is that I thought (probably naively) that ASE staffers might actually be e-mailing or calling the ESO, and could simply put the question about rotational direction to its staffers. "Cosmology" is really the more important tag, but the site had its own rule (possibly alphabetic) for sequencing them. $\endgroup$
    – Edouard
    Commented Mar 13, 2018 at 17:49

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I'm going to say that the answer to the main question is "no", for two reasons.

  1. The Introduction to this recent paper by Naoz et al. mentions a variety of different suggested models and explanations, none of which is based on anything like alternate cosmological models. (The paper itself argues that the apparently problematic distribution of stellar orbits may be an artifact of failing to account for the presence of binary stars, so that the system isn't really anomalous at all.)

  2. It's not at all clear to me how an alternate cosmological model like the one you link to would be even remotely relevant to the details of star formation in the Galactic Center. In other words, I wouldn't expect anyone to be trying to explain star formation near Sgr A* using alternate cosmologies or extensions to GR (the star formation took place mostly well outside the region where GR becomes noticeably different from Newtonian gravity, so modifications to GR would be even less relevant).

As for the second question: we simply don't know the direction or amount of the central supermassive black hole's spin (yet).

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  • $\begingroup$ @ Peter Erwin--Isn't the 6-to-0 ratio of stars to their binary partners in the disk extremely low? $\endgroup$
    – Edouard
    Commented Mar 16, 2018 at 22:08
  • $\begingroup$ @ Peter Erwin--I mentioned the relation of Poplawski's cosmology to GR only to lend it more credibility that it might otherwise have to viewers unfamiliar with it. Because BH's expand outward from the centers of collapsing stars, the appearance of new stars very near such a center would seem consistent with the bounce outward from a spatial center that he's describing. With or without that theory, it's seeming like the majority of our galaxy's stars acquire their binary partners either away from that center, or away from wherever they do form. $\endgroup$
    – Edouard
    Commented Mar 16, 2018 at 22:23
  • $\begingroup$ Also, Naoz seems to be inferring unobserved binaries from the eccentricities of the orbits, but admits that, given the youth of the stars concerned, the eccentricity itself would be hard to explain, all of which seems to be simply shifting one problem to another. Regarding the eccentricity, it might bear a relation to an actual reduction in spatial scale between each iteration of the universe and the next, in the sequence of them hypothesized by P.: Elongation of the separation between paired virtual particles is what produces those of each bounced iteration. $\endgroup$
    – Edouard
    Commented Mar 16, 2018 at 23:30
  • $\begingroup$ Because the bounce from "a spatial center" might otherwise seem to be in conflict with the homogeneity and isotropy "required" by the Cosmological Principal, I need to add that, in Poplawski's view, EACH BH formed by the gravitational collapse of ANY rotating star would appear to be in a past- and future-eternal sequence, which would give the resulting spatio-temporal multiverse twice the spatial extent of that produced by the field-based version of inflation, however abstruse the concept of "double infinity" might appear. $\endgroup$
    – Edouard
    Commented Mar 17, 2018 at 16:10
  • $\begingroup$ @ Edouard -- the point isn't so much "Naoz et al have solved the problem" as an example of how probably no one has bothered trying to use someone's speculative alternate cosmology to explain a localized puzzle involving a few stars. $\endgroup$
    – Peter Erwin
    Commented Mar 17, 2018 at 16:10

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