Many musicians tell stories about how they found the inspiration to write a new composition. Berkeley clarinetist Ben Goldberg has one of better tales about being visited by a muse with a taste for Umbrian aristocracy. In the summer of 2017 he was a Civitella Ranieri artist-in-residence, which entailed hanging out at a 15th-century castle in Italy. He spent part of his time contemplating a book of poetry by previous Civitella Ranieri artist Gjertrud Schnackenberg, Heavenly Questions, and was particularly struck by the opening poem “Archimedes Lullaby,” an extended meditation on the final days of the ancient Greek mathematician. He premieres the evening-length work Archimedes Lullaby Friday at Berkeley’s JCC East Bay with a sensational cast of improvisers including alto saxophonist Kasey Knudsen, keyboardist Michael Coleman, electric guitarist Andrew Conklin, drummer Hamir Atwal, and Jon Arkin on laptop and live electronics (Goldberg, Coleman and Atwal also perform as Invisible Guy at the California Jazz Conservatory May 21).