Hannah Fry

Before this morning, I was quite rusty on quantum spin.

It's been a while.

I'll be honest.

Because people use this phrase, it gets thrown around and in your head I think it conjures up a mental image of a ball that's literally spinning.

It is absolutely not like that at all.

I sort of think in a way it shouldn't be called spin because the analogy

only works really on one level.

We're not talking about physical spin here.

It's more like a property of the particle that's like mass or electric charge, right?

Just in the same ways you can't

take away the mass of an electron, you can't take away its spin either.

It's like a characteristic of it.

But the reason why they've used the word spin is because it's all around how the particle behaves and it's got these similarities to angular momentum.

It's a quantity that gets conserved, essentially.

There's no spinning ball there.

No.

Unless...

There is a way, there is a way to get them to spin, to physically spin.

The thing is, is that you have to remember that like electrons in particular, for example, it's like a teeny tiny little bar magnet, right?

And it has this magnetic field that exists around it and it can align