Approaches to Quantum Gravity

392 R. Gambini and J. Pullin[3] C. Di Bartolo, R. Gambini, R. Porto and J. Pullin, J. Math. Phys. 46, (2005) 012901.[4] C. Di Bartolo, R. Gambini and J. Pullin, Class. Quan. Grav. 19 (2002) 5275.[5] C. Di Bartolo, R. Gambini and J. Pullin, “Consistent and mimetic discretizations ingeneral relativity,” J. Math. Phys. 46 (2005) 032501.[6] C. Di Bartolo, R. Gambini and J. Pullin (2005), in preparation.[7] J. L. Friedman and I. Jack, J. Math. Phys. 27 (1986) 2973.[8] R. Gambini, M. Ponce and J. Pullin, “Consistent discretizations: the Gowdyspacetimes,” Phys. Rev. D 72 (2005) 024031.[9] R. Gambini, R. Porto and J. Pullin, in Recent Developments in Gravity, K. Kokkotas,N. Stergioulas, eds. (Singapore, World Scientific, 2003) [gr-qc/0302064].[10] R. Gambini, R. Porto and J. Pullin, Class. Quant. Grav. 21 (2004) L51.[11] R. Gambini, R. Porto and J. Pullin, New J. Phys. 6 (2004) 45.[12] R. Gambini, R. Porto and J. Pullin, Phys. Rev. D 70 (2004) 124001.[13] R. Gambini, R. Porto and J. Pullin, Braz. J. Phys. 35 (2005) 266.[14] R. Gambini, R. Porto and J. Pullin (2005) ArXiv:quant-ph/0507262.[15] R. Gambini and J. Pullin, Int. J. Mod. Phys. D 12 (2003) 1775.[16] R. Gambini and J. Pullin, Phys. Rev. Lett. 90 (2003) 021301.[17] R. Gambini and J. Pullin, Class. Quant. Grav. 20 (2003) 3341.[18] R. Gambini and J. Pullin, Gen. Rel. Grav. 37 (2005) 1689.[19] R. Gambini, and J. Pullin, “Discrete space-time” (2005), ArXiv:gr-qc/0505023.[20] R. Gambini and J. Pullin, “Consistent canonical classical and quantum Reggecalculus” (2005), ArXiv:gr-qc/0511096.[21] K. Kuchar, “Time and interpretations of quantum gravity”, in Proceedings of the 4thCanadian Conference on General Relativity and Relativistic Astrophysics,G. Kunstatter, D. Vincent and J. Williams, eds. (Singapore, World Scientific, 1992).Online at http://www.phys.lsu.edu/faculty/pullin/kvk.pdf[22] A. Lew, J. Marsden, M. Ortiz and M. West, in Finite Element Methods: 1970’s andBeyond, L. Franca, T. Tezduyar and A. Masud, eds. (Barcelona, CIMNE, 2004).[23] Y. J. Ng and H. van Dam, Annals N. Y. Acad. Sci. 755 (1995) 579[arXiv:hep-th/9406110].[24] Y. J. Ng and H. van Dam, Mod. Phys. Lett.A9 (1994) 335.[25] D. N. Page and W. K. Wootters, Phys. Rev. D 27 (1983) 2885.[26] O. Reula, Living Rev. Rel. 1 (1998) 3.[27] C. Rovelli, Phys. Rev. D 42 (1990) 2638.[28] C. Simon and D. Jaksch, Phys. Rev. A70 (2004) 052104.[29] L. Smolin, The Life of the Cosmos (Oxford, Oxford University Press, 1992).[30] L. Smolin, Class. Quan. Grav. 9 (1994) 173.