ELI5: Explain Like I'm 5

Gregory Chaitin

Okay kiddo, so Gregory Chaitin is a really smart guy who likes to do math. He is famous for something called Chaitin's constant, which is a really long number that tells us how much information is in the universe.

Now, you know how you have a lot of toys and games and things that you like to play with? Well, the universe has a lot of things in it too - like stars, planets, trees, and animals. And just like how you can't count all of your toys, you can't count all of the things in the universe.

But, Chaitin wanted to figure out how much information is in the universe, even if he couldn't count everything in it. So, he came up with a really cool idea to use math to give us an estimate of how much information there is.

He made a really long number (it has over 31 trillion digits!) that tells us how much information there is in the universe. It's called Chaitin's constant. Even though we can't actually write out the whole number because it's too long, Chaitin's constant helps us understand how much information is in the universe.

So, Gregory Chaitin is a really smart guy who used math to estimate how much information is in the universe by creating a really long number called Chaitin's constant.