ELI5: Explain Like I'm 5

Weight (representation theory)

Okay kiddo, let's start with a simple question. What do you think weight means?

Hmm, let me think. Is it something heavy that you can hold in your hands?

That's a good guess, but in math, weight means something different. Specifically, we use weight to help us understand how different parts of a math problem fit together.

So, imagine you're playing with some building blocks. You have a bunch of blocks of different sizes and shapes, and you want to stack them up to make a tower. But you notice that some blocks are heavier than others, and that makes it harder to stack them up in certain ways.

In math, we use weight to help us understand how these blocks fit together. We assign each block a weight based on its size and shape, and then we use those weights to figure out which blocks can be stacked on top of each other.

But here's the tricky thing: sometimes we're not just stacking blocks, we're working with something called a group. A group is like a big math problem made up of lots of smaller parts, and we use weights to understand how those parts fit together.

So when we talk about weight in math, we're really talking about how different parts of a group fit together. We assign each part a weight based on its importance and its relationship to the other parts, and then we use those weights to help us solve the problem.

Does that make sense, little one?

Yes, I think I get it! So weight is like the importance of different parts of a math problem, and we use it to figure out which parts can fit together?

Exactly! You're a smart cookie.