On Monday I started a series of articles to explain particles and fields, aimed at those who’ve had a little bit of physics in their past (perhaps a semester or two just before or just at the beginning level at a university), and containing a very little amount of math.
I first brought you the story of the ball on a spring, both the classical [i.e. pre-quantum] version from the 1700s and the quantum version from the early 1900s.
Now it’s time to turn to waves. This is the longest subject I’ll have to cover, I think, so I split even the pre-quantum story of waves up into two parts, one aimed at getting the right formula for describing a wave, and the other at getting the right equation of motion for which that formula is a solution. If you’ve had first-year physics you’ve seen most of this, but there’s a twist toward the very end that is probably novel — you’ll see a wave equation you’ll probably recognize, but also one that, quite possibly, you haven’t seen before.