Didymus the Musician was a music theorist in Alexandria of the 1st century AD who combined elements of earlier theoretical approaches with an appreciation of the aspect of performance. According to Andrew Barker, his intention was to revive and produce contemporary performances of the music of Greek antiquity. The syntonic comma of 81/80 is sometimes called the comma of Didymus after him.

Reference

Barker, Andrew, Greek Musicologists in the Roman Empire, in Timothy D. Barnes (ed.), The Sciences in Greco-Roman Society, Aperion: A Journal for Ancient Philosophy and Science 27.4 (December 1994).