i've never done a disertation. got my master's in the 1970s: if you showed up to seminars coherent and fully clothed, you got a `b,' and if you could write papers with colonated titles (Bacon and Eggs: Cholesterol Imagery in Howard Johnson's `Menu') the English Department whisked you right on thru. They even let me write a creative work in lieu of research (`All the Way to the Flowers' - one of the great unpublished novels of the Vietnam war). so i gotta tell you, i'm impressed with anyone who could do it in physics in the 1990s. prolly most of the stuff you've had to master wasn't even discovered when i was in school. (we still used the rutherford model of the atom.)
coupla possibilities on why musical equations haven't been tried:
1) it may be a dumb idea. in fact, it may be some little known bit of physicist lore that everyone since the invention of the flute has been approached whilst on the verge of getting their doctorates and asked about setting equations to music. this conversation maybe some ancient rite of passage. so there's that, or...
2) physicists play music off duty and may not connect it with work. or, they're playing german//austrian//sometimes french composers, and physics may sound more like jazz or ragas, a form they may not recognize.
smart money's on no. 1, but it mite be something to try. if it works and you're famous, lemme ghost-write for you. physics pays a whole lot better than daily news (about $10 a pound, if Barnes & Noble is anything to go by, compared with four bits an armload for newspaper.)
must dash. my missus gets back from seattle tonight, and i got about two hours to clean up the house...
warmest...
jlewis