While we wait for Zeuzzz to write his next post (and while I wait for iantresman to reply to my questions, especially the last one ("
Could you please explain, in more detail, what you think Scott's paper includes, in the way of core concepts (see my earlier posts on the distinctions between core concepts and other aspects, referenced in the post you quote), that Ziggurat's (and many others') comments do not address?")), I'd like to introduce another paper which
Zeuzzz cited as a 'plasma cosmology paper published in mainstream astronmy journals':
How Can Spirals Persist? (C.K. Whitney, Astrophysics and Space Science, Volume 227, Issue 1-2, pp. 175-186).
So we have another candidate "plasma cosmology" paper with
zero citations. If this is the state-of-the-art of plasma models of galaxy structure, why isn't it used (and cited) in subsequent discussions? If this is
not the state of the art, why post it as an example of work in the field?
Anyway, not only does no one cite this paper: the author seems deeply unfamiliar with any actual facts of galaxy observation and modeling. First of all, she doesn't even pretend to be aware that there are
mainstream models for the formation and maintainance of spiral arms. It's standard practice in science papers that, if there
is a model/theory/paradigm in competition with yours, you should say so. If the author is indeed aware of these other theories, then her statement in the abstract
The older gravitational models can explain how spirals might form, but they also predict that the spirals would quickly disintegrate.
is flatly false. Neither SSPSF nor Lin-Shu models "predict that the spirals would quickly disintegrate". The author has absolutely no grounds for believing they do; if the paper is meant to "solve this problem" then it is attacking a pure strawman. The alternative is that the author is
unaware of the existence of mainstream models, which is consistent with the fact that she doesn't cite them---but this doesn't exactly inspire confidence in the author's attention to detail.
And then we get to the theory. To generate two spiral arms, the author places a
pair of huge gravitational masses in the Galactic bulge; their symmetry axis is taken to define the initial direction of the arms; the resulting gravitational quadrupole sets up a potential that could accelerate galactic-center stars outwards. At first glance, I think the author is correct to show that this mechanism, so constructed, could indeed result in persistent spirals---it's sort of a limiting case of density-wave theory.
The author makes no attempt whatsoever to compare this model to reality. Are there two giant masses orbiting one another inside the Galactic bulge? Good heavens, no. We've got extremely detailed orbital data (both radial velocities and proper motions) throughout the bulge, and it's not a giant gravitating dumbbell. Are arm/bar stars actually moving radially outwards at a good fraction of their orbital speed, according to observations? No no no no. The model is thus
completely refuted. End of story.
The other odd things about the paper are the long digression about electromagnetism, which is presented as though there's an elaborate analogy between gravity and E&M, but in the end the analogy
isn't used in the paper except insofar as the author uses a finite-propagation-speed gravity model; it reads like a badly-padded undergrad lab report, where there's an extra two pages on the Zeroth Law of Thermodynamics appended to the statement "We stored the E. Coli in liquid nitrogen at 77K." The author cites Peratt's plasma simulations and
points out that they're irrelevant to astronomy because stars are neutral, which is perfectly true. That's something, anyway.