Druj Aeterni is a large chamber ensemble piece that seeks to unify two of my musical identities: Composer and Bassist. Three of my intellectual pursuits and interests ancient mythology, cosmology, and mathematics inspired me to compose this piece. The title of the piece uses Latin and the language of the Avesta, the holy book of Zoroastrianism, and comments upon a philosophical perspective based in string theory. I abstract the cosmological implications of string theory, apply them to the terminology and theology of Zoroastrianism, and then structure the composition in consideration of a possible reconciliation.