Heller M, Woodin W.H. (eds.) Infinity. New research frontiers (CUP, 2011)(ISBN 1107003873)(O)(327s)_MAml_

eferences 191universe is initially finite, because the dynamics of inflation, played out over an infiniteavailable duration, allow the creation of an infinite universe – even, in a sense, manysuch universes. Thus, although we cannot prove that the universe is infinite, strongevidence for inflation, along with the (strong but imperfect) theoretical link betweeninflation and “everlasting” inflation, leads to a strong inference of an infinite universe.On even more speculative ground, I have discussed the possibility that in cosmology,finity might be problematic in certain ways, so that the very coherence and comprehensibilityof our physical world is pointing to an infinite duration, or infinite numberof states of the universe. Even if this conclusion is overreaching, however, the analysisof the paradoxes or solutions to paradoxes that infinity can generate in cosmology canbring novel perspectives on some ancient riddles.AcknowledgmentsI am grateful to the organizers of the “Infinity” workshop, Ellipsis Enterprises, inconnection with which this paper was prepared. I also am grateful to Matt Johnson,Steven Gratton, and Max Tegmark for their company in banging our heads against someof the riddles of cosmological infinities. I thank Michael Heller for helpful commentson the manuscript.ReferencesAguirre, A., and Gratton, S. 2002. Phys. Rev. D65, 083507.Aguirre, A., and Gratton, S. 2003. Phys. Rev. D67, 083515.Aguirre, A. 2007. arXiv hep-th, URL http://arxiv.org/abs/0712.0571v1.Aguirre, A., Johnson, M. C., and Shomer, A. 2007a. Phys. Rev. D76, 063509.Aguirre, A., Gratton, S., and Johnson, M. C. 2007b. Phys. Rev. D75, 123501.Aguirre, A., Gratton, S., and Johnson, M. C. 2007c. Phys. Rev. Lett. 98, 131301.Aguirre, A., and Johnson, M. C. 2008. Physical Review D77, 123536, (c) 2008: The AmericanPhysical Society.Aguirre, A., and Tegmark, M. 2005. JCAP 0501, 003.Banks, T., and Fischler, W. 2004. arXiv hep-th, URL http://arxiv.org/abs/hep-th/0412097v1.Bondi, H., and Gold, T. 1948. Monthly Notices of the Royal Astronomical Society 108, 252.Borde, A., and Vilenkin, A. 1996. Int. J. Mod. Phys. D5, 813.Borde, A., Guth, A. H., and Vilenkin, A. 2003. Phys. Rev. Lett. 90, 151301.Bousso, R. 2006. arXiv hep-th, URL http://arxiv.org/abs/hep-th/0605263v4.Bousso, R., Freivogel, B., and Yang, I.-S. 2006a. Phys. Rev. D74, 103516.Bousso, R., Freivogel, B., and Lippert, M. 2006b. Phys. Rev. D74, 046008.Bousso, R., Freivogel, B., and Yang, I.-S. 2007a. arXiv hep-th, URL http://arxiv.org/abs/0712.3324v3.Bousso, R., Harnik, R., Kribs, G. D., and Perez, G. 2007b. arXiv hep-th, 38 pages, 9 figures, minorcorrection in Figure 8.2, URL http://arxiv.org/abs/hep-th/0702115v3.Carroll, S. M., and Chen, J. 2004. arXiv hep-th, URL http://arxiv.org/abs/hep-th/0410270v1.Chang, S., Kleban, M., and Levi, T. S. 2007. arXiv hep-th, URL http://arxiv.org/abs/0712.2261v1.Coleman, S. R., and Luccia, F. D. 1980. Phys. Rev. D21, 3305.Douglas, M. R. 2003. JHEP 05, 046.