The word Pithoprakta translates to "actions through probability".
Gaussian distribution of temperature fluctuation.[3]
This theory states that "the temperature of a gas derives from the independent movement of its molecules." Xenakis drew an analogy between the movement of a gas molecule through space and that of a string instrument through its pitch range.
To construct the seething movement of the piece, he governed the 'molecules' according to a coherent sequence of imaginary temperatures and pressures. Brownian motion is a four-dimensional phenomenon (three spatial dimensions and time), and Xenakis created the score by first creating a two-dimensional graph, necessitating some simplifications.
ordinates (y) represent pitch at 1 semitone = .25 cm,[3] when transcribed into musical notation 5 cm = 1 measure.[4] This length is subdivided into three, four, and five equal parts, allowing for fine differences in duration[3] but also creating a steady pulse in each instrumental part, reducing the rhythm of the random walk to steady footsteps. Composer Simon Emmerson notes that this regularity is "impossible in reality and fails to use his ‘stochastic’ approach in this instance."[4] Each part gets nowhere, but as a whole the mass's pitch is freely modulated and its speed-determined "temperature" varies.[3]
^Ilias Chrissochoidis, Stavros Houliaras, and Christos Mitsakis, "Set theory in Xenakis' EONTA", in International Symposium Iannis Xenakis, ed. Anastasia Georgaki and Makis Solomos (Athens: The National and Kapodistrian University, 2005), 241–249.
