[Physics] Can plasma turn back into gas, solid, or liquid

plasma-physicssolid-state-physicsstates-of-matter

I wanted to know if, since basic chemistry teaches you that states of matter can be changed, I was wondering particularly about plasma.

I know that virtually all of the Sun is plasma, so I was wondering if it's possible to de-ionize the sun, and convert it into a liquid and melt it?

I realize this question is laughable, but if the Sun is made out of plasma, and it is converted into a liquid, would there be any immediate benefit in drinking it?

Like, what nutritional value would there be in drinking the Sun? I realize this is going off topic to dietary/nutritional concerns, but as physicists can't we all take a step down?

Now, I hope you are all aware that this question is meant to be both enjoyable and scientifically credible, so please don't jump the gun and attempt to ionize my question.

Best Answer

Sometime a plasma is called the fourth state of matter, in the sense that to go from the gaseous phase to the plasma phase you have to provide enough energy to ionize the atoms/molecules of the gas; this energy can be seen as the "Latent Heat" you need for the phase transition.

However, this is not a satisfactory way of thinking of a plasma. For instance, the plasmas created in high power laser-matter interaction (as a reference, this is a very good book by P. Gibbon), have number densities of the order of $10^{23} cm^{-3}$, so well in the solid state density regime. Anyway, at even higher densities (and very high temperature) a plasma (the solar plasma, for instance) can have dynamical properties which resembles very much those of a liquid, in the sense that a fluid mechanical description (or MHD, if the plasma is magnetized) captures its dynamics.

For the sake of curiosity, there are even studies on "ultracold plasmas", which have very remarkable properties like the fact that if they are let expand while cooling, they can crystallize and form ordered structures called Coulomb crystals (you can look here if you're curious). A phase transition like that, from plasma to solid, is an even higher step than sublimation!

From the nutritional point of view, if you consider that a spoonful of a neutron star nucleus is more massive than the entire Earth, I think you'll need some billion of years of gym to get your silhouette back again!