Each of the 24 modes in the Ramanujan function corresponds to a physical vibration of a string. Whenever the string executes its complex motions in space-time by splitting and recombining, a large number of highly sophisticated mathematical identities must be satisfied. These are precisely the mathematical identities discovered by Ramanujan.
Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the Tenth Dimension (ed. Oxford University Press, USA, 1995) - ISBN: 9780192861894