Beltrami flow

Let's say you have a piece of paper that has a very specific shape on it - it could be a square, a triangle, or any other shape. Now, imagine you wanted to stretch and bend the paper so that its original shape changes.

Beltrami flow is a math concept that explains how we can change the shape of the paper, while keeping certain parts of it the same. It's kind of like stretching and bending the paper, but with some rules.

The rule is: when you bend or stretch the paper, you have to keep the way certain parts of it are connected. For example, if there are two points on the paper that are connected by a straight line, after the bending and stretching, those two points still have to be connected by a straight line.

Beltrami flow is important in many areas of science, because it helps us understand how objects, like the Earth's surface or the shape of a liquid, can change while keeping some important qualities the same. Overall, it's a way of transforming objects in a specific way, but maintaining some of their original features.