ELI5: Explain Like I'm 5

timeline of bordism

Okay little friend, so a long time ago mathematicians discovered something called topology. It's all about shapes and how they can be transformed without changing their basic properties.

One part of topology is called bordism, which is like a way of measuring and comparing different shapes. But instead of just looking at the shapes themselves, we look at all the ways they could fit together with other shapes.

So imagine you have a ball and a cube, and you want to compare them using bordism. You could try to fit the cube into the ball, but it's too big. Then you could try to squash the ball to make it fit into the cube, but it's too small. So those shapes aren't bordant - they can't fit together in any way that doesn't change their basic properties.

But say you have a big ball and a small ball. You can totally fit the small ball inside the big one, so they're bordant.

Now, over time mathematicians discovered more and more things about bordism, like how to classify different types of shapes based on their bordism properties. They could even make a timeline of all the important discoveries, like when someone figured out how to use bordism to study the space that shapes live in.

So basically, bordism is a way of comparing different shapes and seeing how they can fit together. And mathematicians have learned a lot about it over time, like how to use it to understand the properties of different shapes and how they relate to each other. Cool, huh?