# Learning to Multiply by Ten – or How I Ended up Here

Christmas looms – my PhD is complete (bar printing my final hardbound copies), and my research is tied up in way too neat a bow to start new tasks today.  So I have decided to keep it Science-y today, and talk about where I began this journey, and the moment I became a scientist.

The moment I became a scientist was actually a Maths moment. I was in primary school, and we had just learned our multiplication tables.  I had struggled to learn them, and my Dad had been drafted in to help me.  Every day after school, we worked through every table from 2 to 9, and eventually when the teacher made us stand up and recite them, I was mercifully able to get through to the end.

Then we learned about multiplying by 10.  I can remember feeling nervous about having another table to learn, and it was a two-figure table at that.  How on Earth was I supposed to learn this?

It was then that the teacher told us that there wasn’t any point in learning the 10 times table – all you had to do was add a zero to the number you were multiplying.  The hundred times table – add two zeroes.  Thousand – add three.  A million? Add six. I couldn’t help but feel like this was some sort of witchcraft.  There were no tables to recite.  How did it work?

Then I had a watershed moment.  I started to realise that you didn’t do Maths by rote, with tables and number lines.  Maths had rules, just like language did.  If you spoke Maths, you could do whatever you liked with it. It was then I understood that Maths had a power of its own, and it was then that I realised that I wanted to know all the rules of Maths.  I started to find rules of my own in the multiplication tables – like if you take any of the first ten entries in the 9 times table and add their digits, the sum is 9; or that the 5 times table entries always ended with 5 or zero; or that anything multiplied by 2 was even, and anything multiplied by two plus one was odd.  They might seem pretty elementary to most, but to me they were magic, like the Universe was revealing its innermost secrets to me.

I went on to learn more about the rules of Maths, and a chance encounter with a incredibly good substitute Physics teacher (Mr Munro, wherever you are, thank you!) set my mind on learning about the rules of Physics, which are written in the language of Maths.  Over the years, I’ve found again and again that there was always another Eureka moment in store for me as I learned more about Science.  Whether it was how calculus could take you from acceleration to distance, or how light waves burst out of Maxwell’s equations, or how Euler’s Identity  $e^{i\pi} + 1 = 0$ neatly wraps the Universe’s most fundamental constants into one very simple equation, or how Noether’s Theorem links symmetries and conservation laws, or how Einstein’s Theory of General Relativity links geometry and dynamics, there was always another thing to learn about that took me aback.

And there will always be another thing I haven’t learned yet that will still take me aback.  And that is how I ended up here, as a research scientist.

Merry Christmas, everyone!