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posted by on Sunday January 22 2017, @07:52AM   Printer-friendly
from the baryon-chauvinists dept.

According to this paper [PDF], the calculations of spiral galaxy spin which required the dark matter fudge factor were oversimplified. If you actually model the spiral arms in detail the results match observations without the need for dark matter:

"Abstract The gravity fields and rotation curves of whirlpool galaxies with thin disc distribution of material are calculated numerically. It is proved that the gravity field of mass thin disc distribution is greatly different from that of spherically symmetrical distribution. As long as the Newtonian theory of gravity is used strictly, by the proper mass distributions of thin discs, the flat rotation curves of whirlpool galaxies can be explained well. The rotating curve of the Milky Galaxy is obtained which coincides with practical observation. In this way, it is unnecessary for us to suppose the existence of additional dark material in the illuminant discs of whirlpool galaxy again. Meanwhile, in the space outside the illuminant disc, the quantity of dark material needed to maintain the flatness of rotation curves is greatly decreased. By considering the observation fact that the quantity of non-luminous baryon material is 3~10 times more than luminous material, we can explain the flatness of rotation curves of whirlpool galaxies well without the hypotheses of non-baryon dark material. So it is unnecessary for us to suppose that non-baryon dark material is about 5 times more than baryon material in a single whirlpool galaxy, no mater [sic] whether non-baryon dark material exits or not."


Original Submission

 
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  • (Score: 5, Informative) by maxwell demon on Sunday January 22 2017, @08:46AM

    by maxwell demon (1608) on Sunday January 22 2017, @08:46AM (#457289) Journal

    This is a link to an arXiv preprint. Such links should always go to the abstract page [arxiv.org] instead. The PDF is only a click away from the abstract page, but the reverse is much harder.

    Looking at the arXiv page, you see that this paper has been submitted in March 2009, but has no journal link, indicating that this article probably was never published in a refereed journal. A search for the title in Google Scholar confirms this.

    Also note that from the arxiv abstract page, you'll also learn if the authors update or retract their paper (neither of this has happened to the paper in question, but you couldn't tell from the PDF link, only from the abstract link).

    Maybe someone could implement a filter in Rehash against links to arxiv.org or its subdomains which are ending in ".pdf"?

    --
    The Tao of math: The numbers you can count are not the real numbers.
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  • (Score: 0) by Anonymous Coward on Sunday January 22 2017, @03:39PM

    by Anonymous Coward on Sunday January 22 2017, @03:39PM (#457347)

    or its subdomains which are ending in ".pdf"?

    That solves your issues with arXiv linking, but it would cause problems with submissions that are linking to a PDF for other reasons.

    • (Score: 3, Informative) by maxwell demon on Sunday January 22 2017, @04:37PM

      by maxwell demon (1608) on Sunday January 22 2017, @04:37PM (#457363) Journal

      Please read the complete sentence. It was a connection of two conditions:

      1. Link to arxiv.org or one of its subdomains
      2. ends in .pdf

      Therefore PDFs links to other sites than arXiv would not be affected.

      --
      The Tao of math: The numbers you can count are not the real numbers.
  • (Score: 2) by mhajicek on Sunday January 22 2017, @05:29PM

    by mhajicek (51) on Sunday January 22 2017, @05:29PM (#457382)

    I apologize, I'm not familiar with all of that. I was sent only a link to the PDF and thought I would share it.

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    The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek