Well, since none of the students have replied yet, I will mention that I am a mathematics professor. After completing my Ph.D. in pure mathematics (in a branch of abstract algebra known as "Commutative Ring Theory"), I began researching interdisciplinary connections with music. This remains my current primary academic interest.
So, A LOT of new ideas and studies occur after graduation! 
That's awesome, I'd be interested, if you can put something quite simplified about what you are researching.
Oh, and philosophy here.
Writing "on the fly", I am working on models of voice-leading that are based on algebraic rules as opposed to classical harmonic principles. One of my research colleagues has used some of the models to demonstrate structural unity in four-part array writing in the music of Igor Stravinsky, a context in which "traditional" approaches to music theory did not provide much information.
I am going to be offline for a couple of days, but I will write down a VERY simplified post of some actual mathematical ideas in this research area in a week or so. My handle, "knetfan", derives from the primary tool used in my research: the "Klumpenhouwer network". A scholar by the name of Klumpenhouwer created this mathematical tool and presented it in his doctoral thesis (music theory) in 1991.
Sixth form is the same as college.
As per my post of September 21 --- much more than a week later 
--- I will now offer a couple of ways to think algebraically about the motion of musical voices.
1. Establish a "distance" between two pitches. In Western compositional practice, the obvious choice for the basic unit is the semitone; e.g., the distance from D to D# is 1 semitone while the distance from F to G# is 3 semitones.
2. Music theorists usually require that a description of a relationship between a pair of notes be based on some form of audible phenomenon. Two common ways to perceive the relationship of an F to an A are as follows:
2a. A transposition will interpret the movement to be linear in either an ascending or descending path. Thus, the F could move UP 4 semitones to the A or the A could move DOWN 4 semitones to the F.
2b. An inversion will interpret the movement to be a symmetrical leap around a pitch in the middle. Thus, the F would be the inversion of A around G, and vice versa, because both F and A are 2 semitones away from G in opposite directions. The point is that if the listener starts at G, he or she can hear (with practice) a simultaneous movement of tones in opposite directions. By the time the ascending note rises from G to A, the descending note will simultaneously arrive at F. Thus, F and A are inversionally related.
3. A Klumpenhouwer network is an algebraic/graphical tool that describes the "quality" of pitch clusters by breaking down the various pitches in the cluster into pairs and identifying the possible transpositional and inversional relationships among the pairs. Thus, a "trichord" --- a pitch cluster consisting of three notes --- has three pairs of pitches within it. So, the "quality" of the trichord might be described using one transposition and two inversional relations. Because the underlying transpositions and inversions have audible significance, mathematicians and music theorists are able to work together to arrive at richer interpretations of the voice-leading capabilities inherent in a "trichord" or in a pitch cluster with more than three notes.
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It will go way beyond the scope of this message board to post more here. A relatively elementary introduction to the theory of Klumpenhouwer Networks can be found in the following reference:
Lewin, David. “Klumpenhouwer Networks and Some Isographies that Involve Them.” Music Theory Spectrum 12/1 (1990): 83-120.
I went to college for a business degree but majored in beer drinking instead. (Bachelor's)
My college days are long gone, but I'm just curious what you're studying.