It was Mrs B's birthday so I made her some bunting. The first time I've used a sewing machine in four decades. This is what happens when you watch the Sewing Bee. It brought to mind a saying that I struggled to understand as a child: "A stitch in time saves nine." It took means years to realise that "in time" meant "in the nick of time" rather than "in the fabric of time itself". So I used to imagine there being a stitch somehow in the minutes and hours. First: what is time, actually? One physics teacher told me that it is that quantity which allows two objects to occupy the same spacial coordinates... think about it! Time for Einstein was just another dimension that could be stretched. That takes some thinking about. I've been trying to get my maths up to General Relativity standard recently so I'll let you know. But there is a problem trying to reconcile gravitational theories with quantum theory. When things get very small, quantum effects take over. The uncertainty principle means that eventually things are so close together that you can't tell whether you have two locations or one. This tiny length is called the Planck Length. The time it takes light to cross this distance is called the Planck Time. This may well be the smallest unit of time and that you can't meaningfully have smaller divisions. If so, then perhaps this is my stitch in time.
