Does the type of fluid influence the physics of liquid rotation?
It should certainly form the parabola shape but there may be distortion at the edge due to surface tension effects. However (I found in ref. 1) it wets glass, so it may have low enough surface tension for this not to be much of a problem. I wonder if you have investigated the possibility of (1) using mercury, which seems to be the material of choice among astronomers who build rotating liquid mirrors (see ref. 2), and (2) using a near-parabolic container (e.g., a bowl) rather than a pan so that only a thin layer of the reflecting liquid is needed. Maybe you’ve already looked into this. Mercury would seem a good choice since you don’t have to heat it and it’s highly reflective like gallium.
