ELI5: Explain Like I'm 5

Cotangent complex

Okay, so first let's talk about tangents. Imagine you're drawing a curve or a circle on a piece of paper. At any point on that curve, you can draw a line that just touches the curve. That's the tangent.

Now, imagine you have a bunch of curves all intersecting at different points. The way they intersect can tell you a lot about the shape of the whole thing. But it can also get complicated – what if the curves aren't smooth, or they intersect at weird angles?

That's where the cotangent complex comes in. It's a way of measuring how bumpy or complicated the intersection of different curves is. You can think of it like a special tool that helps you understand the shape of things that are tangled up with each other.

But wait, what's "complex" mean? It just means that it's made up of a bunch of parts that work together in a certain way. So the cotangent complex is made up of different "pieces" that help you figure out how the curves are intersecting.

Now, this might all sound very abstract and complicated. And truthfully, it is! The cotangent complex is a pretty advanced concept in mathematics. But it's also really useful for lots of different fields, like geometry, topology, and physics. So even if you don't fully understand it right now, just remember that it's a tool that helps people study some of the most complex and interesting shapes in the world.