Kirszbraun theorem
Kirszbraun theorem is kind of like a puzzle game. Imagine you have two shapes, like a ball and a cube. You have a special rule that says you can stretch the ball or the cube as much as you want, but you can't change the overall shape or size.
Now, let's say you draw lines on the ball and the cube to show where they touch each other. Kirszbraun theorem says that you can always find a way to stretch the ball and the cube so that the lines are still touching, but the ball is touching the cube in more places than before.
This might sound like a silly game, but it's actually really important for mathematics. It helps us understand how to work with shapes and measurements in different ways. And even though it's a hard theorem to prove, lots of smart people have done it, so we know it's true!
Now, let's say you draw lines on the ball and the cube to show where they touch each other. Kirszbraun theorem says that you can always find a way to stretch the ball and the cube so that the lines are still touching, but the ball is touching the cube in more places than before.
This might sound like a silly game, but it's actually really important for mathematics. It helps us understand how to work with shapes and measurements in different ways. And even though it's a hard theorem to prove, lots of smart people have done it, so we know it's true!