ELI5: Explain Like I'm 5

Homology theory

Okay, kiddo! Today we're going to learn about homology theory. Imagine you have two things that are kind of similar, like a donut and a coffee cup. They both have holes in the middle! But they're also different because the donut is all round and the cup is a cylinder shape.

Homology theory is a way to compare different shapes and see how similar they really are. We can do this by breaking them down into smaller parts, like slices of the donut or pieces of the cup. These parts are called "simplices".

We can also imagine stretching, twisting, or bending these shapes to see if they can be transformed into each other. If we can transform one shape into the other, then they are said to be "homologous".

Homology theory helps mathematicians understand how different shapes are related to each other and can be used in many different branches of math and science. Pretty cool, huh?