This is inspired by this question.
What is the maximum volume that can be enclosed by folding a square piece of paper (with side length $\ell$) using only (rigid) Origami moves?
I found this, but it's not very helpful because it doesn't give a specific volume and I can't find the paper it references.
It's not a question I think I can answer myself. I have no formal training in Origami and know very little about it.
I'm guessing the shape is just a cube but I'm not sure how to prove that.
Please help :)