My younger daughter is blessed with a very good spatial ability, which I am sadly lacking in. I just couldn’t see things in three-dimensional space, much as I trained myself to in the past. This child of mine, from a very young age, always had to explain things to her dim mum.

We knew that there is something extraordinary going on in her brain when our family friend, who is a Maths teacher, showed her how to make a tetrahexaflaxagon. Here is an explanation of the simpler flaxagon: https://en.wikipedia.org/wiki/Flexagon

Not only did she cotton on how to fold one instantly, we could see that her understanding of 3-D space was almost intuitive. We layered on the complexity by adding in time, and again, the challenge was easy for her. As I tutor her in Physics, Chemistry and Maths, I realised that at the tender age of 14, she had outgrown me. She would often pick up errors in her school textbooks which her teachers and I fail to notice – probably because we never look beyond the immediate, whilst she is always ten steps ahead.

I cheekily sneaked Einstein’s relativity into our tutorials without actually telling her the significance of what I was teaching her.

“Not sure about that,” she said in her direct manner, “But I know it is this.” And deftly squiggled and using childish language, clarified geometry. It took Einstein eight years to find the relationship between the geometry of space-time and physics; it took this child the context of IGCSE Physics to see the beginnings of this profound relationship.

Though I was delighted for her to be blessed with such a brain, I was slightly deflated for myself, I must admit. Here, in the form of simple graphics, is Einstein’s special relativity explained.

And my child’s question to you is this:

Your friend Roger is travelling at just a fraction below the speed of light and he is holding a mirror. Since nothing can travel faster than the speed of light (in normal conditions), can Roger see his own reflection? Can you see Roger’s reflection, if you are standing on earth?

Note: Don’t email me the answers! Just buy Catching Infinity when it comes out!