I'm saying that dusty plasmas collapse into stars because of an electrostatic body force. In a recent number crunching exercise, I found that a Debye cell, with a negatively charged dust grain and a positively charged sheath, exerts a slight repulsion on other nearby cells. Debye cells are net neutral, and wouldn't interact electrically at all with neighboring cells, except for the fact that they have positive charges around the outsides. This means that the closest thing to one Debye sheath is the sheath of another cell, and both are positively charged. Since the electric force obeys the inverse square law, if you add up all of the repulsions and attractions, the net force is a slight repulsion, due to the greater proximity of the sheaths to each other. But I also found that if something strips the sheaths off of the dust grains, the net body force goes from slightly repulsive to massively attractive.
As an analogy, imagine that you're going to lay some floor tile in a typical alternating pattern of blacks & whites. So your assistant starts opening up the boxes of tiles, and making little piles of an even number of blacks & whites, equally spaced across the floor, knowing that as you start setting the tiles, you'll need equal quantities of both. If blacks & whites were oppositely charged ions, each pile would be net neutral, and there would be no net force between the piles. But as you start setting the tiles in the alternating pattern, that changes. Each white tile gets only black tiles for neighbors, and vice versa for the black tiles. If those were opposite charges, there would be nothing but attraction between the tiles. And since each tile would be attracted to all of its neighbors, all of the forces added up would constitute a body force on the whole thing, which would cause an implosion. (This is why OSHA stipulates that ions should never be used for floor tiles -- it just isn't safe.)
So what does it take to strip Debye sheaths off of their dust grains, to create this implosive body force in a dusty plasma?
The two conditions known to trigger star formation are supernovae, and the collision of two dust clouds. In both cases, the sheaths would get stripped. This is because the smaller particles in the sheaths have less inertia and experience more friction, while the heavier dust grains have more inertia and less friction. Thus they behave differently when exposed to a contrary flow, from a supernova or another gas cloud.
What does this have to do with filaments?
When two gases collide, they don't just merge smoothly. Rather, jets tend to form, if the velocity is above the Reynolds number (i.e., lots of inertia and/or not a lot of friction). In a relativistic collision of plasma thinner than a laboratory vacuum, we'd call that a very high Reynolds number. Anyway, the jets allow the inertia to be preserved with minimal friction, because only the outside of the jet is in contact with the other medium. The Pillars of Creation, in the Eagle Nebula, looks exactly like this typical fluid dynamic phenomenon. It's also a stellar nursery.
So you're saying that the stars are forming around the outsides of the filaments. Are we talking about the same thing? Maybe. If the "filaments" are relativistic jets, tunneling through another medium because they are well above the Reynolds number, the friction is around the outside of the jets. And friction strips Debye sheaths off of dust particles, resulting in an electrostatic body force on the dusty plasma. The interior of the jets experience no friction, and thus their Debye cells remain well formed, and repel each other. So the star formation should be around the outside of the jets/filaments.
