Eddie Wu

And that circle is the shape of the rainbow that you and I see.

It's just that we usually only see half of it because the horizon is blocking its path.

But this unlocks one of those beautiful things about rainbows, which is that if you and I, Mike, were standing right next to each other,

We would both look up and see a rainbow in the sky, but we'd both be seeing different rainbows because you see a different set of raindrops to me.

So Newton was one of the first people.

Sir Isaac Newton explored this law of cooling, which is that, as you mentioned, temperature, which is really the measurement of heat energy, which is every little atom around you vibrating at a different frequency.

that's an amount of energy that wants to be shared it wants to be diffused throughout a zone now the reason why that's mathematics is because we can use that diffusion of heat in a very predictable way to know things like for example crime scene investigators when they want to know the exact time of death of a victim they can say well we actually know what temperature a human body is

when it's alive and it will very predictably drop off at a certain rate.

So if we measure the temperature of that body, we can actually with a great degree of accuracy know if this happened within a certain number of hours, we can even pin down the time of death.

So to me, this very predictable mathematical model, it's called exponential decay, starts off very steep and the temperature drops rapidly and then it sort of levels out and becomes this sort of gradual curve.

This is a mathematical idea that we can use to, again, interpret and understand the world around us.

Again, you don't need to know the formal mathematics to intuitively get that.

When you brew a cup of coffee or pop in a cup of tea, it quickly goes from maximum temperature, boiling, steaming, down to a temperature that's actually one you can drink.

Then, of course, it drops further and becomes a little bit uncomfortable.

You probably want to warm it up again.

This idea is very intuitive to all of us and that's because it's a mathematical pattern that we experience over and over again and our brains, our minds are attuned to.

100%, Mike.

And one of the things I used to imagine as a kid is this invisible bucket brigade.

I don't know if you've got this picture in your mind of all these different people sort of passing water one to another using a string of buckets.

Well, that's exactly what atoms are doing.