The mathematical relationships embedded in Bach's scores in general, and that of the Goldberg Variations in particular, have been observed by many authors previously but their potential extrapolation beyond compositional dimensions to issues of performance have rarely been considered. This chapter reflects upon the performance of Bach's Goldberg Variations the authors presented in a version for two pianos at the Mathemusical Conversations Workshop. It transpired that the prospect of performance in a mathemusical context encouraged a form of experimentation in the rehearsal process which proved highly stimulating to the performers' musical imaginations. The talk delivered at the conference anticipated the performance but this chapter includes some analysis and reflections subsequent to the performance itself.

At both a metaphorical and a conceptual level, central mathematical fields—arithmetic, probability, geometry and algebra—offered starting points for some intriguing interpretative possibilities and conundrums for modeling potential interpretative choices at both micro and macro levels, pertinent perhaps not only for Bach but also for more generic performance applications. Inspired in particular by Einstein's work on Relativity and the mathematical formulations which became central to its articulation, we came to conceive of the score as an equation, its variables opening up to interpretation through performance. Rather than seeking fixed performance solutions, however, our current perception is that such mathematical modeling can open up creative possibilities for freedom and play.

That performers are rarely explicit about interpretative influences in their performances or in their rehearsal process, particularly those less obviously intrinsic to the work itself, may be due to several factors of which the following occur to us: the belief that the piece in performance “speaks for itself”; that the ephemeral nature of a particular performance limits the value of its study; or that the perceptions are too subjective, too momentary or conjectural, to be of value. This chapter however offers an alternative perspective, that music could be argued to most fully present when a particular performance is inspired equally by its more transitory or flexible dimensions (here described as the variables) as by aspects which are more fixed in their nature. Arguably, its ephemeral transformable nature is perhaps one of the core elements of music's identity, meaning and value.