Today's guest is Tom Crawford, a mathematician you might recognize from some of our number file videos and his own channel, Tom Rocks Maths.

Tom specialises in applied mathematics and has a PhD in fluid dynamics from Cambridge.

These days, he's teaching students at Oxford University and has carved out an unusual niche doing outreach.

Oh, and occasionally, he teaches mathematics wearing only his underwear.

But we'll get to that later.

You don't look like a mathematician, do you?

Like, are people surprised when you're...

Yes, yeah, yeah, no. I...

Fair point.

I think you're right.

I wouldn't look like the typical mathematician.

But at the same time, I often like to counter that point by saying, well, what does a mathematician look like?

To me, it's someone who's as maths.

Like in any other aspect of life, that can be literally anybody. Yeah. But like, for people who can't see you and haven't seen you on number file, like you have lots of tattoos, admittedly a lot of them are mathematical tattoos. Yes. But you might not know that at first, like lots of tattoos, and you've got your cool trendy long hair and lots of piercings and things like that.

What do people normally think you do? Like, what do people guess? I used to play this game with my friends actually when I was a graduate student. So we'd go out on these things in Cambridge, they're called Swaps. Basically, you have a group of guys, group of girls. You all go out for a meal together and sit boy, girl, around the table.

Like, organized fun, we used to call it. We used to always have a laugh, was that when you're, you know, you're sat down, you're introducing yourself. I'd often be sat in my friend Joe, and we'd say, what do you think each of us does? Because he looked very similar to me. He did chemistry and I did maths. and everyone would guess English, art was quite popular.

Occasionally like history. I don't really, I don't know, but it was more something that I

think had an element of creativity, at least that people would think of as a creative type subject.

But yeah, not so many guesses on maths. Well, let's go back to the start then.

Let's go back in time a bit. Where were you born? Warrington, northwest England. It's about

halfway between Liverpool and Manchester. I say near Manchester when I introduced myself to people

because of football allegiances. When I was growing up at school, it was either you were a Liverpool

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