It didn't need Albert Einstein or Stephen Hawking to alert me to this. I've been aware of it for donkeys' years; all they had to do was to ask me.

Take clocks, for example. We divide the face into 12 equal sectors, so each will be 30 degrees. (Why we never decimalised them into 10 hour days I'll never know. Brexit, probably. But that's beside the point).

The point is each hour doesn't occupy 30 deg per half day – they're far more elastic than that. And everyone that works will know it. They'll know that when they're on holiwags or at weekends time travels twice as fast. When they're at work, twice as slow. When you're seven it takes an eternity for you to become 8, but when you're 70 the 10 years to becoming 80 last about 3 months.

I don't know how much research Einstein and Hawking put into this; I don't know if resources included using the Hadron Colander; I don't know if the project involved American and Russian collaboration.

All I can say is they should have asked me.