<s>[INST] Soap films are thin layers of liquid with two interfaces, explained by Plateau's rules. Researchers have built a framework using a number of "idealized" soap films to study these interfaces. They have published research explaining that:
"In the case of cylindrical soap films, two unbroken circular bases that resisted stretching during their height maximizing experiment are supported by an infinite film that does not sag (does not experience gravity). In short, the chosen soap film stabilizes into an idealized cylinder."
Research shows that the film is an idealized example of the soap film stabilizing into a shape that minimizes surface area. In the surface physics world of soap films it's called the "minimax principle" [1].
The minimax principle by soap film are as follows:
1. Soap films stabilize by intuitively taking the form which minimizes surface area under the constraints provided by their attached objects.
2. In the vicinity of the developible regions surface, a small perturbation (small unbalanced force) along the surface creates a pressure sort of force towards the original interface [1].
In the experiment described above, what was the surface that was minimax principle utilized?[/INST]