Here's an article imparting Einstein's obsession with Mozart, along with the similarities between what Einstein said about Mozart's music and his own idea of the cosmos.
More can be found in the Issacson biography of Einstein, which I don't presently have on hand. Mozart's music seems to have convinced Einstein that whatever theory ultimately successfully described the cosmos would have to have a grace, succinctness, and beauty that corresponded to the grace, succinctness, and beauty of Mozart. In the case of Einstein, as I am sure you are aware, this worked to his advantage and against it; for it when he discarded superfluous ad hoc physical constructions such as the luminiferous ether in favor of c's constancy, and of course against it when he constructed the cosmological constant to satisfy his intuition that the universe was eternally static. You can say that his interpretation of Mozart's music as perfect, succinct, and eternal could have simply been a matter of his subjective feelings on the matter, and of course I would agree with you. However, I'm not sure that music's subjective nature necessarily negates its usefulness as a model for mathematical aesthetics. If Beethoven pleases me, I'll look for solutions that satisfy me in a similar fashion. If those solutions work, they work, and nobody has grounds to gainsay my assertion that musical aesthetics informed my judgment.
http://www.nytimes.com/2006/01/31/science/31essa.html
More can be found in the Issacson biography of Einstein, which I don't presently have on hand. Mozart's music seems to have convinced Einstein that whatever theory ultimately successfully described the cosmos would have to have a grace, succinctness, and beauty that corresponded to the grace, succinctness, and beauty of Mozart. In the case of Einstein, as I am sure you are aware, this worked to his advantage and against it; for it when he discarded superfluous ad hoc physical constructions such as the luminiferous ether in favor of c's constancy, and of course against it when he constructed the cosmological constant to satisfy his intuition that the universe was eternally static. You can say that his interpretation of Mozart's music as perfect, succinct, and eternal could have simply been a matter of his subjective feelings on the matter, and of course I would agree with you. However, I'm not sure that music's subjective nature necessarily negates its usefulness as a model for mathematical aesthetics. If Beethoven pleases me, I'll look for solutions that satisfy me in a similar fashion. If those solutions work, they work, and nobody has grounds to gainsay my assertion that musical aesthetics informed my judgment.