Xenakis was a composer. One of his compositional techniques involved using stochastic laws to derive pitches played by stringed instruments (that was one of his parameter mapping strategies).
But what I find interesting is that he used real world physical events to help structure or order musical events in time. This is very similar to my concept of ‘composition by physical determinism‘. Except in my instance I am actually attempting to model (in a virtual-reality-esque way) the actual physical positions and movements of sonic events in time.
Xenakis was inspired by sounds structured in line with his (sonic) experience of mass-demonstrations in Athens after the second world war. This excerpt is taken from his book “Formalised Music: thought and mathematics in composition” 1992 (page 9). Its a brilliant description of a real-world event that can be used as a skeleton for structuring sound in time (i.e. composing).
Everyone has observed the sonic phenomena of a political crowd of dozens or hundreds of thousands of people. The human river shouts a slogan in a uniform rhythm. Then another slogan springs from the head of the demonstration; it spreads towards the tail, replacing the first. A wave of transition thus passes from the head to the tail. The clamor fills the city, and the inhibiting force of voice and rhythm reaches a climax. It is an event of great power and beauty in its ferocity. Then the impact between the demonstrators and the enemy occurs. The perfect rhythm of the last slogan breaks up in a huge cluster of chaotic shouts, which also spreads to the tail. Imagine, in addition, the reports of dozens of machine guns and the whistle of bullets adding their punctuations to this total disorder. The crowd is then rapidly dispersed, and after sonic and visual hell follows a detonating calm, full of despair, dust, and death. The statistical laws of these events, separated from their political or moral context, are the same as those of the cicadas or the rain. They are the laws of the passage from complete order to total disorder in a continuous or explosive manner. They are stochastic laws.
I’m not entirely sure which of Xenakis’ compositions (if any) was directly inspired by this description of events, but Pithoprakta must come close (in the sense that one can imagine the dynamic of crowds):