A very unclear and puzzling article. With a bodacious claim. The photograph leaves much to be explained. What is the circle? Why is it offset? Is sulfur gas the only thing in the sphere? Is sulfur the only element that is ionized? Is the MW cw or pulse? What F is the sound? Where is the 1000g force applied in the photograph?
Can it be tuned to a higher g force? Can the same be done with other elements? Can the same principle be applied to raw naked plasma? Or just ionized gas?
If we can hold plasma in a ball at that force, it ought to help us with fusion and other containment functions. Even if it's just ionized gas, the 1000 g figure is impressive.
I am going to speculate that the sound waves served to compress the gas from all sides at the same time, similar to what a central gravity field would do on the Sun. The time for observation would be very short.
From the paper's abstract: "...a high amplitude, spherically symmetric acoustic wave in a rotating spherical bulb containing weakly ionized sulfur gas."
Any "acoustic" wave has periods of high pressure and low pressure. Maybe they time their movie camera to photograph it during the high pressure pulses. Maybe they set up standing waves. Don't really know.
I must have mis-understood the process. I thought they said they heated gaseous sulfur in a glass sphere, then MW radiated and ionized the gas. The sound from the hot ionized particles corralled the particles in the center of the sphere, with a simulated force of 1000 g.
I assumed it was steady state as long as the MW was applied. I thought the only input was the MW.
As I read it, the microwaves did the ionization and the sound waves did the compression. The compression stimulated convection which resulted in the flow patterns they photographed.
Convection in spinning spherical conductive fluids undergoing convection is very complex. There are Coriolis forces, covective forces and magnetic forces to consider. In the Sun, the result is the 22 year solar cycle with many layers of covective cells extending from equator to poles.
Magnetic forces are particularly hard to understand since a conductive fluid moving through a magnetic field generates a current that makes a magnetic field that directly opposes the field that created it.