Schlessinger's theorem

Schlessinger's Theorem is like a magic trick that helps to understand something called deformations. Have you ever played with playdough or clay? Deformation is like when you take the playdough and squish it with your fingers to make it look different. Schlessinger's Theorem helps you figure out if you can squish one shape (like a circle) into a different shape (like a square) while keeping certain important things the same.

It's like a rule that says if you have a certain kind of shape, and you want to squish it into a different shape in a certain way, then you can do it if and only if some special math thing is true called the Ext group.

Let's say you have a balloon in the shape of a circle, and you want to squish it into the shape of a square without popping it. You have to be very careful! Schlessinger's theorem is like a magic spell that helps you know if it's possible to do it without breaking anything, and how to do it without popping or breaking the balloon.

Just like you need to know how to read to do your homework, people who study math and science need to use the Ext group to do certain kinds of math homework. And Schlessinger's Theorem helps them know when to use this Ext group. It's a very special tool that helps you know whether you can deform one shape into another shape, and how to do it without breaking anything important.