2002)cite arxiv:astro-ph/0210527Comment: 34 pages including 10 figures. To appear in "Science and Ultimate Reality: From Quantum to Cosmos", honoring John Wheeler's 90th birthday. J. D. Barrow, P.C.W. Davies, & C.L. Harper eds. Cambridge University Press (2003) V3: Final version submitted to the editors. Differences from V2: Only added references and fixed typos.