ELI5: Explain Like I'm 5

Lebesgue covering dimension

Okay, imagine you have a big, flat piece of land and you want to know how much space it takes up. But instead of just measuring it directly, you're going to use something called "Lebesgue covering dimension".

Think of this like covering the land with a bunch of different sizes of paper cut in different shapes. Each piece of paper has to completely cover some part of the land, but it can also overlap with other pieces of paper.

Now, you want to know how many different sizes of paper you need to completely cover the land. This is the Lebesgue covering dimension - it's how many different "levels" of paper you need to use.

But here's the tricky part: the paper can be any shape, and it doesn't have to be the same shape for each level. So you might use big, flat rectangles for the first level, then smaller squares for the second level, and tiny triangles for the third level.

The important thing is that every single point on the land is covered by at least one piece of paper at every level. This means that no matter how detailed or complex the shape of the land is, you can always find a set of paper shapes that will cover it completely.

So the Lebesgue covering dimension is a way of measuring how complex a space is, by figuring out how many different "levels" of detail you need to fully describe it. And it's useful in a lot of different branches of math and science, where people need to understand the structure of very complex systems.