Nomos Alpha (1966) is a piece for solo cello composed by Iannis Xenakis in 1965, commissioned by Radio Bremen for cellist Siegfried Palm , and dedicated to mathematicians Aristoxenus of Tarentum, Evariste Galois, and Felix Klein (DeLio 1985, p.xii).

The structure is in part, Level I, determined by group theory, specifically the 24 element octahedral group structure and is in 24 sections, with each fourth section, Level II, not being determined by group stucture and rather a "continuous evolution of register" (ibid, p.23).

Sources

• DeLio, Thomas, ed. (1985). Contiguous Lines: Issues and Ideas in the Music of the '60's and '70's. ISBN 0819143308.
  • DeLio, Thomas. "The Dialectics of Structure and Materials: Iannis Xenakis' Nomos Alpha".
• Xenakis, Iannis (1971). Formalized Music, p.219-236. Bloomington, Indiana: Indiana University Press.