ELI5: Explain Like I'm 5

Wiles's proof of Fermat's Last Theorem

Okay kiddo, let’s talk about something called Fermat’s Last Theorem. A long, long time ago, a man named Pierre de Fermat wrote down a problem in his notebook that said: there are no whole number solutions to the equation x^n + y^n = z^n when n is bigger than 2.

This was called Fermat’s Last Theorem because he said he had a proof for it but didn’t write it down. For over 350 years, people tried to solve the problem, but no one could find a solution.

That is, until a man named Andrew Wiles came along.

But how did he do it? Well, he used a lot of complicated math, but what he basically did was find a way to turn the equation from Fermat’s Last Theorem into another equation using something called modular forms.

He worked on this proof for years and years, and when he finally announced that he found a solution, all the mathematicians around the world cheered because this was one of the biggest unsolved problems in math history!

In short, Andrew Wiles found a way to solve a super hard math problem that had been unsolvable for centuries. He used a lot of numbers and formulas to do it and he had to think really hard for a very long time. But he did it!