Terence Tao

But we can't prove that.

Yeah, I guess it's not mysterious that the planets are being random because there's no reason for them to have any kind of secret pattern.

But what is mysterious is what is the mechanism that really forces the randomness to happen.

And this is just absent.

Oh, yeah.

So it's a problem that you can explain.

It helps with some visual aids.

So you take any natural number, like, say, 13, and you apply the following procedure to it.

So if it's even, you divide it by 2.

And if it's odd, you multiply it by 3 and add 1.

So even numbers get smaller, odd numbers get bigger.

So 13 will become 40, because 13 times 3 is 39, add 1, you get 40.

So it's a simple process.

For odd numbers and even numbers, they're both very easy operations.

And then you put them together, it's still reasonably simple.

But then you ask what happens when you iterate it.

You take the output that you just got and feed it back in.

So 13 becomes 40.

40 is now even, divided by 2 is 20.

20 is still even, divided by 2 is 10.