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Galaxies
© Charles Chandler
 
Figure 1. NGC 1427A
 
Figure 2. ESO 325-G004
 
Figure 3. NGC 1344
 
Figure 4. NGC 5866
 
Figure 5. NGC 4565
 
Figure 6. NGC 628
 
Figure 7. PRC D-51
 
Figure 8. IC 883
Dusty plasmas condense into stars, planets, & moons. A big enough clump of stars makes a galaxy. The so-called "peculiar galaxies" (such as in Figure 1) are random assemblies of stars in no particular form. And the motion of stars within the clump is random. But there are three other principle types of galaxies that are much more organized: the ellipticals, the lenticulars, and the spirals.1
 
The ellipticals (as in Figure 2) are actually ellipsoids (i.e., 3D ellipses). The motion of stars within the galaxy appears to be more radial than rotational, though the rotational component appears to vary with the aspect ratio (i.e., major axis over minor axis). Hence nearly spherical galaxies have no detectable average rotation, and the principle motion is radial (inward or outward). The greater the aspect ratio, the more consistently all of the stars rotate in the same direction.
 
The stars in elliptical galaxies appear to be much older than in spiral galaxies, since there is very little gas & dust between them. In other words, the accretion process is nearly complete, meaning that ellipticals have been in this configuration for a long time. The age is also implied by the dominance of dim yellow stars, and the absence of bright blue stars, if stars slide down the Hertzsprung-Russell diagram with age. (See the section on the Main Sequence.) Nevertheless, ellipticals (such as NGC 4486 and NGC 383) sometimes shoot out relativistic jets from their active galactic nuclei, and ellipticals are the only galaxies that emit bipolar radio source jets, revealing powerful energy conversions still going on inside these ancient galaxies.
 
Lenticulars (such as in Figure 4) are similar to ellipticals in many ways.
  • They have elliptical forms.
  • The galactic boundaries are indistinct.
  • They are comprised mainly of old stars.
  • There is very little interstellar plasma.
  • The consistency of rotation varies with the aspect ratio.
For these reasons, many scientists consider lenticulars to be related to ellipticals, just with higher aspect ratios. The main difference is that lenticulars have a distinct disc made of dust. This makes them similar to spiral galaxies, except that the dust is not organized into discrete lanes.
 
Spirals (such as our own Milky Way, and NGC 4565 in Figure 5) typically have a central, elliptical bulge, which has many properties in common with elliptical galaxies (i.e., old stars on semi-random orbits around the center, and without much interstellar plasma). The distinguishing characteristics of spirals are that almost all of the stars outside of the central bulge are on the plane of rotation, and when viewed normal to the plane (as in Figure 6), we see that they are organized into spiral arms, dominated by young blue stars, especially on the leading edge of the arms.
 
Interestingly, these galactic forms are evolving. A recent study revealed that in the early Universe, there were far more peculiar galaxies, and now, there are far more spirals.2 (See Figure 9.) This means that peculiars are evolving into spirals. Furthermore, the number of ellipticals & lenticulars has remained relatively constant, meaning that peculiars first got organized into ellipticals, then lenticulars, and finally, into spirals.
 
 
Figure 9. Distribution of galaxy types, 6 billion years ago versus now.
 
 
So the random forms and motions within peculiars are getting coerced into unison. In spirals, the progression is nearly complete. This is clear evidence of an organizing principle. It takes force to alter the motions of stars and planets. Anything that can alter the paths of most of the matter in a galaxy is a force of galactic proportions. So what is that force?
 
First we can consider how peculiars could get morphed into ellipticals. One possibility is that the peculiars imploded and subsequently exploded. No matter how irregular the shape, there will always be a centroid, which will be the focal point of an implosion. And the ejecta from the resulting explosion will radiate outward in a spherical pattern. Of course, if all of the matter reached the centroid at the same time, it would produce ejecta that would radiate outward in a shell. This does happen (see Figure 3), but it is the exception rather than the rule. So it's more typical that the "explosions" occur over an extended period of time, producing steady streams of matter that account for the smooth density gradient. Indirect evidence of the in/out motion comes from the study of galaxies 9 billion years ago (as determined by the redshift) — half of the most massive galaxies were over an order of magnitude more dense than galaxies today.3 With time, we'd expect everything to get closer to the hydrostatic equilibrium. The implication is that long ago, more of the galaxies were not at equilibrium, meaning that they were either imploding or exploding. Since the compact galaxies are dominated by old stars, we should suspect that these were old galaxies at the end of their cycles (i.e., imploding).
 
What is the force that causes the implosion?
 
Figure 10. Debye sheaths stretched into comas by friction.
The key to this is the conditions in which the force emerges — elliptical galaxies are formed when two or more smaller galaxies merge.4 In Newtonian mechanics, this wouldn't be the expectation — two or more irregular shapes would merge into an even more complex irregularity. But the section on Accretion demonstrated that a collision of two clouds containing charged particles generates a linear body force that causes the collapse of the cloud. (See Figure 10.) And if it's true about negatively charged Debye nuclei surrounded by positively charged sheaths, it must also be true of negatively charged stars surrounded by positively charged interplanetary media. So the force that causes the implosion when galaxies merge is electrostatic. The main difference is just that the implosion of Debye cells might produce a star, but the implosion of all of the stars in a galaxy isn't going to create one huge star, because there is a limit to how much matter can be packed into a single aggregate before the pressure initiates a runaway thermonuclear explosion (i.e., a supernova). So instead, the galactic implosion results in a spherical explosion.
 
Having established similitude between Debye cells and stars in principle, we can then see how many other pieces in the star formation model apply to galaxy formation.
 
First, the linear implosion necessarily prescribes a filamented form (as described in the section on Filaments). And this is a typical form for galactic mergers. (See Figure 8.) Furthermore, stars frequently appear like "beads on a string" along dusty plasma filaments, and likewise the earliest active galaxies, while still what we would call peculiar, often appear as chains of distinct clumps.5
 
Second, we observed that at the point of implosion, the two halves of the filament oppose each other, for both electric and magnetic reasons. (See Figure 11.) The EM braking figures significantly in preventing the filaments from simply tunneling through each other, and rather, coming to a full stop at the point of implosion. Likewise for galactic filaments, the matter should be able to counter-stream without collisions, begging the question of why galaxies would merge and not just slip past each other, and the answer is EM braking.
 
Third, the EM braking might result in the filaments glancing off of each other on collision, in which case rotation is induced. The degree of angular momentum will then determine the aspect ratio of the new galaxy, from nearly spherical galaxies with almost no net rotation, to spiral galaxies with nothing but rotation.
 
Figure 12. Galaxies rotate on planes that point to nearby voids, courtesy Gabriel Pérez (Servicio SMM del IAC).
Fourth, we observed that one of the triggers for star formation is a supernova, whose radial ejecta stretch Debye sheaths into comas, generating linear body forces. This might create a series of star formation filaments all pointing at the location of the supernova. (See, for example, the inner ring of SN 1987A in Figure 13.) Now we can observe that galaxies tend to spin on planes that are aligned to voids.6 (See Figure 12.) This is tough to explain, until we consider the possibility that the void was cleared out by an explosion. This would have produced radial ejecta, which would have created filaments pointing at the center of the void. When those filaments imploded to form galaxies, if any rotation was generated, one of the axes of the plane of rotation would have to be pointed at the void.
 
Finally, it's even possible that the imploding galactic filament would split into negative and positive charge streams, which could resolve into a continuous toroid. (See Figure 14.) This might explain the formation of ring galaxies, such as in Figure 7. Note that the twist in the ring makes sense only in EM terms, where counter-streaming particles generate a magnetic field that induces a spin due to the Lorentz force.
 
Now we should consider what could possibly produce a disc as flat as that in Figure 5. The lay literature frequently likens this to the flattening of pizza dough when twirled in the air. This is actually a good metaphor, as the centrifugal force will, indeed, stretch the shape. But in a critical analysis, we realize that there also has to be some sort of tensile strength, or it will fly apart. If we cut the dough into pieces and try to twirl it, we'll just make a mess of the place. So where do we get the tensile strength to hold together a galaxy?
 
It isn't gravity, and that's by definition. Gravity is a function of mass, and so is the centrifugal force, and these two forces cancel each other out — they don't fight each other, and yield tensile strength as a by-product. Additional gravity from CDM doesn't help, at least not if it's conventional matter (albeit surprisingly cold and dark), whose mass would also have its own centrifugal force. (Heavier chunks of dough still fly apart if they are twirled at the same speed.) We have to find a fundamental physical force that operates at the macroscopic level (ruling out the strong & weak nuclear forces), that isn't a direct function of mass (ruling out gravity), and that can exert an attractive force. The only remaining candidate is electromagnetism. If EM can be attractive, we have our answer. And sure enough, in a "like-likes-like" configuration, the electric force is attractive, so this is what provides the tensile strength that allows a galaxy to be twirled into a flat disc without falling apart.
 
Figure 15. Rotation curve of a typical spiral galaxy. The distance is from the galactic center of gravity.
To be more specific, the outer reaches of spiral galaxies rotate 5 times faster than what is predicted by the laws of gravity, as shown in Figure 15. For objects to remain in orbit around the center of gravity, the centrifugal force developed by their orbital speeds has to match the force of gravity exactly. If the centrifugal force is greater, the objects fly away. If it is less, the objects fall inward. Since the spiral arms are stable, this can only be evidence of a non-Newtonian force, 5 times more powerful than gravity. We know that the planets are negatively charged, surrounded by positively charged ionospheres, and we know that the interplanetary medium is plasma with a slight positive charge. Subsequent sections will demonstrate that stars have a net negative charge. So the "like-likes-like" force is definitely present, and could easily be 5 times greater than gravity.
 
And lastly, we would like to know what causes the filamentary arms in spiral galaxies. When we see the cyclonic pattern as in Figure 6, we immediately think of a whirlpool that is pulling matter inward. But we should distinguish between observation and explanation. These are not lines of motion — they're filaments. An inward force would create a cyclonic inflow, but what causes the filamentary nature of the inflow (if it is inflow)?
 
Some EM theorists have attributed this to the magnetic pinch effect, wherein the matter is flowing inward at such a rapid rate that enclosing magnetic fields consolidate the matter into filaments. But the magnetic field lines in spiral arms tend to run parallel to the arms, and are not wrapping around the arms, pinching them into filaments.
 
Figure 16. "Snap the Whip" (Winslow Homer, 1872).
So it's not gravity, and it's not the magnetic force. That leaves the electric force. The most plausible answer is simply that this is yet another manifestation of the "like-likes-like" force, which gets stronger when the matter is drawn into filaments (as presented in the Filaments section). So the same centrifugal force that flattens the disc also stretches the matter into strands that have the tensile force necessary to keep them from flying off. In other words, spiral arms are like the so-called "whipper snappers" who play a child's game in an open field. (See Figure 16.) They start by holding hands and running around in a circle, with the heaviest kid anchoring the center. The centrifugal force stretches the line tight, so they try to hold on as tightly as they can, while the angular velocity at the outer end of the line eventually exceeds the rate at which the child can pedal his/her feet, resulting in a child somersaulting across the field. The contention about spiral galaxies is that the tensile force is supplied by the "like-likes-like" configuration, while the centrifugal force stretches the matter into filaments, and anything rotating too fast has already been released.
 
It's even possible that the "like-likes-like" principle is responsible for the bars that connect many spiral arms to the elliptical bulges in the centers of the galaxies. (See Figure 17.) The arms themselves are in centrifugal-centripetal equilibrium, given the inertial, gravitational, and electric forces at play. And so are the stars in the elliptical bulges. But where the bulge and the arms are nearest to each other, we see a mutual attraction, creating a central bar. This is an expected property if there is a charge separation between solids and their atmospheres, even if there is no net charge separation in each stellar system, much less any EM fields between the arms and the bulges.
 
 
Figure 17. NGC 1300, a barred spiral galaxy.
 
 
With this framework we can now solve the "winding" problem. Essentially, the inner aspects of the arms should be traveling faster, so that they will have more centrifugal force, and will not fall into the center. But if they are traveling faster, they should wrap around the galactic nucleus. So why don't spiral arms typically do this?
 
The answer might be that this isn't a simple cyclonic inflow, and it might not even be an inflow. The spiral arms are whipper snappers, and the ends are traveling much faster than they should, while the tensile strength within the arms keeps them from flying away.
 
But that begs another question. If the arms are whipper snappers, then eventually, the extra centrifugal force out at the end should get the arms fully outstretched, with the arms pointing straight at the galactic nucleus. Only if the arms encounter friction would they curl backwards, despite the centrifugal force. So is there any reason to think that there is any friction?
 
Actually, there is. The interstellar medium is not a pure vacuum — it has something like 0.35 atoms/cm3. What if we're swinging an arm through this medium? We'll generate particle collisions (i.e., friction) that will slow down the arm, and the effect will be proportional to the speed and the density of the interstellar plasma. Now look closely at the lower arm of NGC 1300. The leading edge of the arm sports young, blue-white stars, while the trailing edge has old, yellow stars. This has led some researchers to conclude that there is some sort of shock wave rotating around the galaxy, and where the pressure is higher, stars are condensing, and when the shock wave moves on, the stars fall apart again.7 But that's non-physical, since the shock wave would actually propagate radially — it wouldn't rotate around the center, and we have a better answer. The arms are whipper snappers plowing through plasma, and new stars are forming on the leading edge, where matter is compressed by the collisions. The trailing edge is shielded from all of this, and has only the old stars from when the filament first formed.*19025
 
Figure 18. PIA06237, a small moon of Saturn in the middle of the Keeler gap, courtesy NASA.
A related phenomenon might be planetary rings. No combination of gravity and hydrostatic pressure produces rings, so these are manifestations of EM. If there is an electrostatic body force within a collection of objects, rings are a prediction. The centrifugal force from the axial rotation sends the objects outward, while gravity pulls them back in. With just those two factors taken into account, all manner of circular, eccentric, and non-equatorial orbits are possible. But if we throw in electrostatics, we get a regulated spacing between the objects. This allows the centrifugal force to send everything outward, but electrostatics provides a tensile force that gets the particles to stretch into a perfectly flat disc. So it's like twirling pizza dough.
 
In summary, galaxies condense due to the "like-likes-like" principle. The resulting galactic explosions transform peculiar galaxies in spherical forms. Magnetic pressure induces rotation, which transforms sphericals ultimately into spirals. There doesn't appear to be a limit to the size of galaxies, and small galaxies can eventually merge into large ones. The nature of galactic clusters, and larger cosmological discontinuities, were not investigated.
 
   
 

References

1. Hubble, E. P. (1936): The Realm of the Nebulae. New York: Dover Publications

2. Delgado-Serrano, R. et al. (2010): How was the Hubble sequence 6 Gyr ago? Astronomy and Astrophysics, 509 (A78): 1-11

3. Toft, S. et al. (2014): Sub-millimeter galaxies as progenitors of compact quiescent galaxies. arXiv.org, astro-ph: 1401.1510

4. Barnes, J. E. (1989): Evolution of compact groups and the formation of elliptical galaxies. Nature, 338 (6211): 123-126

5. Keel, B. (2016): High-redshift radio galaxies in the early Universe.

6. Trujillo, I.; Carretero, C.; Patiri, S. G. (2006): Detection of the effect of cosmological large-scale structure on the orientation of galaxies. arxiv, L111-L114

7. Lin, C. C.; Shu, F. H. (1964): On the Spiral Structure of Disk Galaxies. The Astrophysical Journal, 140: 646


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