Wednesday, January 06, 2010

Snow in Reading

I'm now on Chapter 6 of "A First Course in String Theory" and surprised to find that string-theory strings are both like and unlike "normal" violin-type strings. They're alike in that the same equations involving mass per unit length and tension are used; unlike in that the points on a string (excepting the end-points) are not meant to be observationally-distinguishable. This will have consequences, but I haven't got that far yet!

I would get more out of this course if I had studied differential geometry. The text does not demand it but I know enough to recognise that the approach taken is suffused with its concepts. In my plan for the OU maths MSc course I get to differential geometry in the third year, 2012.

The other main foundation of the early chapters has been a central use of stationary values of the action to derive equations of motion. The mathematics behind this, also not explicitly signposted, is the calculus of variations which happily I am about to start.

While I was worrying through the math, Clare was listening to Shostakovich as part of her OU course (pictured below) and trying to work out whether the particular piece in question is in 4/4 time or not. I used to know such things but I've forgotten, and S. is not incredibly melodic which means that neither of us really know. This only matters to one of us though.

It's been snowing here again (as everywhere else in the UK) so here's the video.

video