Imagine you have a big number, like 90. If you want to split it into smaller pieces, you could say it's equal to 50 and 40, because 50 and 40 add up to 90.
But what if you want to split it into smaller pieces in a different way? Maybe you could say it's equal to 30 and 60, or 10 and 80.
This is kind of what Tate's Thesis is about, but with much bigger numbers that have a lot more possible ways to be split up. It's like a puzzle, where you have to figure out all the different ways you can break up a big number into smaller pieces.
But why does anyone care? Well, some mathematicians study these puzzles because they are related to really big and important things like prime numbers (which are like building blocks for all other numbers). By figuring out all the ways you can break up a number, you might be able to learn something important about how prime numbers work.
Overall, Tate's Thesis is a really hard puzzle that only a few really smart people understand, but it's important because it helps us learn more about how numbers work.