ELI5: Explain Like I'm 5

Gödel's speed-up theorem

Okay kiddo, let me explain Gödel's speed-up theorem in a simple way.

Do you remember when we learned about algorithms in math class? An algorithm is a set of instructions that tells you what to do step by step to solve a problem.

Now imagine you have two algorithms, A and B, and you want to compare how fast they are. You could run them on a computer and measure the time it takes for each algorithm to solve the same problem.

But Gödel's speed-up theorem says that there's a trick to make algorithm A run faster than algorithm B, even though A and B are doing the same thing.

How does it work? Well, imagine you have a third algorithm, C, that can help you speed up A. Algorithm C takes as input any algorithm, like A for example, and returns a new version of that algorithm that runs faster.

So you take algorithm A and feed it into algorithm C, which returns a new version of A that runs faster. Let's call this faster version of A "A prime". Now you compare A prime with algorithm B, and you'll find that A prime runs faster than B.

But wait, there's more! You can repeat this process and feed A prime into algorithm C again, getting an even faster version of A called "A double-prime". And if you compare A double-prime with algorithm B, you'll find that A double-prime runs even faster than A prime, which means it's also faster than algorithm B.

This process can continue indefinitely, with each iteration creating a faster and faster version of A. This is Gödel's speed-up theorem in action. It tells us that there's no limit to how fast we can make an algorithm run, as long as we're allowed to use a helper algorithm like C.

So why is this important? Well, it shows us that there's a fundamental limit to what we can achieve with algorithms. No matter how smart or clever we are, we can always find a problem that is difficult enough to require a huge amount of time to solve. But Gödel's speed-up theorem tells us that we can always make our algorithms run faster, as long as we're willing to use helper algorithms to do so.

Does that make sense, kiddo?