“My point was that the field didn’t have to be that strong, only strong enough to “herd” the interstellar gas and dust into “clouds” that conformed to the magnetic field. The stars then formed where the gas was.”
Yes, and also, the electromagnetic effects and gravitational effects don’t have to be exclusive causes. They’re complimentary phenomena, so their effects can combine together and both be responsible, in part, for our observations.
Also, plasma can exhibit self-organizing behavior, when it is arranged in such a way to create recursive feedback. That’s not exclusive to plasma, but is common to all sorts of things that can be so arranged. The principle of induction means that an ionized plasma exposed to a moving magnetic field will result in a current induced in the plasma. When an electrical current is induced, that itself creates a magnetic field surrounding the plasma, which can interact with both the inducing magnetic field and the charged plasma itself, and so on, and so forth, ad infinitum. This type of recursion, mathematically, is always present any time you see fractal shapes appearing, like we see in the galaxies. It’s the key to non-conscious matter and energy arranging itself into optimal patterns.
So, if a cloud of weakly ionized gas passes by a star, galaxy, cluster or any body with a magnetic field, it is like knocking over a domino. It can start a chain reaction of electromagnetic interactions which can result in the plasma changing from a disordered cloud, moving unguided in one direction, to an oscillating magnetically contained body that is subject to a whole variety of subtle, harmonically arranged, electromagnetic interactions.
One of those interactions, the “pinch” phenomenon, can itself compress matter, even to the point of fusion, without the need for gravitational compression. So, starting a simple domino effect caused by induction, a gas cloud could conceivably begin taking the shape of a galaxy and kickstart the process of star formation. That’s not to say that all the gravitational interactions that could cause star formation and self-organization wouldn’t also be happening, just that the two could be working together in tandem.
Many of these things I did not know, but they all make sense. Thank you. If there is a problem with astronomy, it is that the theories are not easily subject to laboratory replication because the scale of size and time is too great, and we don’t have all the data to put into any given theory. For example, we don’t really know if the center of Hercules A is one massive black hole, or several black holes.
Scientists will try to come up with various means of trying to “fit” new data that becomes available into their existing favorite theory. To me, the prime example is “dark matter” and “dark energy.” I have a strong suspicion that those theories are being propounded to explain away inconvenient observations that are actually proving that some generally accepted theories of underlying universal constants are simply wrong.