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Why Do We Want a Theory of Quantum Gravity?

Published online by Cambridge University Press:  28 February 2025

Karen Crowther
Affiliation:
Universitetet i Oslo

Summary

The search for a new scientific theory is typically prompted by an encounter with something in the world that cannot be explained by current theories. This is not the case for the search for a theory of quantum gravity, which has been primarily motivated by theoretical and philosophical concerns. This Element introduces some of the motivations for seeking a theory of quantum gravity, with the aim of instigating a more critical perspective on how they are used in defining and constraining the theory sought. These motivations include unification, incompatibilities between general relativity and quantum field theory, consistency, singularity resolution, and results from black hole thermodynamics.
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Online ISBN: 9781108878074
Publisher: Cambridge University Press
Print publication: 27 March 2025

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References

Adlam, E. (2022). Tabletop experiments for quantum gravity are also tests of the interpretation of quantum mechanics. Foundations of Physics, 52(115), 143.CrossRefGoogle Scholar
Adlam, E. (2023). Are entropy bounds epistemic? arXiv:2303.10781v3 [physics.hist-ph].Google Scholar
Aharony, O., Marsano, J., Minwalla, S., Papadodimas, K., & Van Raamsdonk, M. (2004). The Hagedorn - deconfinement phase transition in weakly coupled large N gauge theories. Advances in Theoretical and Mathematical Physics, 8, 603696.CrossRefGoogle Scholar
Almheiri, A., Hartman, T., Maldacena, J., Shaghoulian, E., & Tajdini, A. (2020). Replica wormholes and the entropy of hawking radiation. Journal of High Energy Physics, 2020(5), 142.CrossRefGoogle Scholar
Almheiri, A., Hartman, T., Maldacena, J., Shaghoulian, E., & Tajdini, A. (2021). The entropy of hawking radiation. Reviews of Modern Physics, 93, 035002.CrossRefGoogle Scholar
Ambjørn, J., Jurkiewicz, J., & Loll, R. (2006). The universe from scratch. Contemporary Physics, 47(2), 103117.CrossRefGoogle Scholar
Ambjørn, J., Jurkiewicz, J., & Loll, R. (2009). Quantum gravity: The art of building spacetime. In Oriti, D. (Ed.), Approaches to Quantum Gravity (pp. 341359). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Anderson, E. (2017). The Problem of Time: Quantum Mechanics versus Special Relativity. Cham: Springer.CrossRefGoogle Scholar
Ashtekar, A. (1995). Mathematical problems of non-perturbative quantum general relativity. In Julia, B. & Zinn-Justin, J. (Eds.), Les Houches, Session LVII, 1992: Gravitation and Quantizations (pp. 181283). Amsterdam: Elsevier Science.Google Scholar
Ashtekar, A. (2005). The winding road to quantum gravity. Current Science, 89, 20642074.Google Scholar
Ashtekar, A. & Geroch, R. (1974). Quantum theory and gravitation. Reports on Progress in Physics, 37, 12111256.CrossRefGoogle Scholar
Bain, J. (2008). Condensed matter physics and the nature of spacetime. In Dieks, D. (Ed.), The Ontology of Spacetime II (pp. 301329). Oxford: Elsevier.CrossRefGoogle Scholar
Barbado, L. C., Barceló, C., Garay, L. J., & Jannes, G. (2016). Hawking versus Unruh effects, or the difficulty of slowly crossing a black hole horizon. Journal of High Energy Physics, 2016(10), 161174.CrossRefGoogle Scholar
Barbour, J. (2000). The End of Time. Oxford: Oxford University Press.Google Scholar
Barceló, C., Liberati, S., & Visser, M. (2011). Analogue gravity. Living Reviews in Relativity, 14(3), 1159.CrossRefGoogle ScholarPubMed
Barceló, C., Visser, M., & Liberati, S. (2001). Einstein gravity as an emergent phenomenon? International Journal of Modern Physics D, 10(6), 799806.CrossRefGoogle Scholar
Batterman, R. W. (2018). Autonomy of theories: An explanatory problem. Noûs, 52, 858873.CrossRefGoogle Scholar
Batterman, R. W. (2011). Emergence, singularities, and symmetry breaking. Foundations of Physics, 41, 10311050.CrossRefGoogle Scholar
Bekenstein, J. (1981). A universal upper bound on the entropy to energy ratio for bounded systems. Physical Review D, 23(2), 287.CrossRefGoogle Scholar
Bekenstein, J. D. (1972). Black holes and the second law. Lettere al Nuovo Cimento, 4, 737740.CrossRefGoogle Scholar
Bekenstein, J. D. (1973). Black holes and entropy. Physical Review D, 7(8), 23332346.CrossRefGoogle Scholar
Bekenstein, J. D. (1974). Generalized second law of thermodynamics in black-hole physics. Physical Review D, 9, 32923300.CrossRefGoogle Scholar
Belot, G. (2011). Background-independence. General Relativity and Gravitation, 43(10), 28652884.CrossRefGoogle Scholar
Belot, G., Earman, J., & Ruetsche, L. (1999). The hawking information loss paradox: The anatomy of a controversy. British Journal for the Philosophy of Science, 50(2), 189229.CrossRefGoogle Scholar
Bern, Z. (2002). Perturbative quantum gravity and its relation to gauge theory. Living Reviews in Relativity, 5(5), 157.CrossRefGoogle ScholarPubMed
Bohr, N. & Rosenfeld, L. (1933). Zur frage der messbarkeit der elektromagnetischen feldgrössern. Det Kgl. Danske Videnskabernes Selskab. Mathematisk-fysiske Meddelelser, XII(8), 133.Google Scholar
Bonanno, A., Eichhorn, A., Gies, H., et al. (2020). Critical reflections on asymptotically safe gravity. Frontiers in Physics, 8, 130.CrossRefGoogle Scholar
Bose, S., Mazumdar, A., Morley, G. W., et al. (2017). Spin entanglement witness for quantum gravity. Physical Review Letters, 119, 240401.CrossRefGoogle ScholarPubMed
Bousso, R. (1999). A covariant entropy conjecture. Journal of High Energy Physics, 7.Google Scholar
Bousso, R. (2002). The holographic principle. Reviews of Modern Physics, 74, 825874.CrossRefGoogle Scholar
Brandenberger, R., Mukhanov, V., & Sornborger, A. (1993). Cosmological theory without singularities. Physical Review D, 48, 16291642.CrossRefGoogle ScholarPubMed
Brown, H. (2005). Physical Relativity: Space-Time Structure from a Dynamical Perspective. Oxford: Oxford University Press.CrossRefGoogle Scholar
Burgess, C. P. (2004). Quantum gravity in everyday life: General relativity as an effective field theory. Living Reviews in Relativity, 7(5), 156.CrossRefGoogle Scholar
Butterfield, J. & Bouatta, N. (2015). Renormalization for philosophers. In Bigaj, T. & Wüthrich, C. (Eds.), Metaphysics in Contemporary Physics, Poznan Studies in Philosophy of Science (pp. 437485). Boston: BrillGoogle Scholar
Butterfield, J. & Isham, C. (1999). On the emergence of time in quantum gravity. In Butterfield, J. (Ed.), The Arguments of Time (pp. 116168). Oxford: Oxford University Press.Google Scholar
Butterfield, J. & Isham, C. (2001). Spacetime and the philosophical challenge of quantum gravity. In Callender, C. & Huggett, N. (Eds.), Physics Meets Philosophy at the Planck Scale (pp. 3389). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Calmet, X. & Latosh, B. (1998). Dark matter in quantum gravity. European Physical Journal C, 78(520), 14.Google Scholar
Cao, T. Y. & Schweber, S. S. (1993). The conceptual foundations and the philosophical aspects of renormalization theory. Synthese, 97(1), 33108.CrossRefGoogle Scholar
Caravelli, F. & Markopoulou, F. (2011). Properties of quantum graphity at low temperature. Physical Review D, 84(2), 024002.CrossRefGoogle Scholar
Carlip, S. (2001). Quantum gravity: A progress report. Reports on Progress in Physics, 64(8), 885.CrossRefGoogle Scholar
Chiribella, G. (2020). Quantum superpositions of causal structures. Critical Hermeneutics, 4(special II), 124.Google Scholar
Colella, R., Overhauser, A. W., & Werner, S. A. (1975). Observation of gravitationally induced quantum interference. Physical Review Letters, 34, 14721474.CrossRefGoogle Scholar
Cotler, J. & Strominger, A. (2022). The universe as a quantum encoder. arXiv:2201.11658 [hep-th].Google Scholar
Crowther, K. (2015). Decoupling emergence and reduction in physics. European Journal for Philosophy of Science, 5(3), 419445.CrossRefGoogle Scholar
Crowther, K. (2016). Effective Spacetime: Understanding Emergence in Effective Field Theory and Quantum Gravity. Heidelberg: Springer.CrossRefGoogle Scholar
Crowther, K. (2018). Inter-theory relations in quantum gravity: Correspondence, reduction, and emergence. Studies in History and Philosophy of Modern Physics, 63, 7485.CrossRefGoogle Scholar
Crowther, K. (2019). When do we stop digging? Conditions on a fundamental theory of physics. In Aguirre, A., Foster, B., & Merali, Z. (Eds.), What Is ‘Fundamental’? Cham: Springer, 123133.CrossRefGoogle Scholar
Crowther, K. (2020). What is the point of reduction in science? Erkenntnis, 85(6), 14371460.CrossRefGoogle Scholar
Crowther, K. (2021). Defining a crisis: The roles of principles in the search for a theory of quantum gravity. Synthese, 198(Suppl 14), 34893516.CrossRefGoogle Scholar
Crowther, K. & De Haro, S. (2022). Four attitudes towards singularities in the search for a theory of quantum gravity. In Vassallo, A. (Ed.), The Foundations of Spacetime Physics: Philosophical Perspectives (pp. 223250). London: Routledge.CrossRefGoogle Scholar
Crowther, K. & Linnemann, N. (2019). Renormalizability, fundamentality, and a final theory: The role of UV-completion in the search for quantum gravity. British Journal for the Philosophy of Science, 70(2), 377406.CrossRefGoogle Scholar
Crowther, K., Linnemann, N. S., & Wüthrich, C. (2021). What we cannot learn from analogue experiments. Synthese, 198, 37013726.CrossRefGoogle Scholar
Curiel, E. (1999). The analysis of singular spacetimes. Philosophy of Science, 66(3), 145.CrossRefGoogle Scholar
Curiel, E. (2023). Singularities and black holes. In Zalta, E. N. (Ed.), Stanford Encyclopedia of Philosophy, https://plato.stanford.edu/archives/sum2023/entries/spacetime–singularities/.Google Scholar
Dafermos, M. & Luk, J. (2017). The interior of dynamical vacuum black holes I: The -stability of the Kerr Cauchy horizon. arXiv:1710.01722.Google Scholar
Dardashti, R., Hartmann, S., Thébault, K., & Winsberg, E. (2019). Hawking radiation and analogue experiments: A Bayesian analysis. Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, 67, 111.CrossRefGoogle Scholar
Dardashti, R., Thébault, K., & Winsberg, E. (2017). Confirmation via analogue simulation: What dumb holes could tell us about gravity. British Journal for the Philosophy of Science, 1(68), 5589.CrossRefGoogle Scholar
Dawid, R. (2013). String Theory and the Scientific Method. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
De Haro, S. (2019). The heuristic function of duality. Synthese, 196, 51695203. https://doi.org/10.1007/s11229–018–1708–9.CrossRefGoogle Scholar
De Haro, S. & Butterfield, J. (2021). On symmetry and duality. Synthese, 198(4), 29733013.CrossRefGoogle Scholar
De Haro, S., van Dongen, J., Visser, M., & Butterfield, J. (2020). Conceptual analysis of black hole entropy in string theory. Studies in History and Philosophy of Modern Physics, 69, 82111.CrossRefGoogle Scholar
Dewitt, C. M. & Rickles, D. (2011). The role of gravitation in physics: Report from the 1957 Chapel Hill Conference.Google Scholar
Doboszewski, J. (2019). Relativistic spacetimes and definitions of determinism. European Journal for Philosophy of Science, 9(2), 24.CrossRefGoogle Scholar
Doboszewski, J. (2020). Epistemic holes and determinism in classical general relativity. British Journal for the Philosophy of Science, 71(3), 10931111.CrossRefGoogle Scholar
Donoghue, J. F. (2020). A critique of the asymptotic safety program. Frontiers in Physics, 8, 56.CrossRefGoogle Scholar
Dowker, F. (2020). Being and becoming on the road to quantum gravity: Or, the birth of a baby is not a baby. In Huggett, N., Matsubara, K., & Wüthrich, C. (Eds.), Beyond Spacetime: The Foundations of Quantum Gravity (pp. 133142). Cambridge: Cambridge University Press.Google Scholar
Dvali, G., Giudice, G. F., Gomez, C., & Kehagias, A. (2011). UV-completion by classicalization. Journal of High Energy Physics, 2011(8), 131.CrossRefGoogle Scholar
Dyson, F. W., Eddington, A. S., & Davidson, C. (1920). A determination of the deflection of light by the sun’s gravitational field, from observations made at the total eclipse of May 29, 1919. Philosophical Transactions of the Royal Society of London Series A, 220, 291333.Google Scholar
Earman, J. (1992). Cosmic censorship. PSA: Proceedings, 2, 171180.Google Scholar
Earman, J. (1995). Bangs, Crunches, Whimpers, and Shrieks: Singularities and Acausalities in Relativistic Spacetimes. New York: Oxford University Press.CrossRefGoogle Scholar
Earman, J. (1996). Tolerance for spacetime singularities. Foundations of Physics, 26(5), 623640.CrossRefGoogle Scholar
Earman, J. (2006). The implications of general covariance for the ontology and ideology of spacetime. In Dieks, D. (Ed.), The Ontology of Spacetime (pp. 323). Amsterdam: Elsevier.CrossRefGoogle Scholar
Eichhorn, A. (2019). An asymptotically safe guide to quantum gravity and matter. Frontiers in Astronomy and Space Sciences, 5, 47.CrossRefGoogle Scholar
Ellis, G. F., Meissner, K., & Nicolai, H. (2018). The physics of infinity. Nature Physics, 14, 770772.CrossRefGoogle Scholar
Eppley, K. & Hannah, E. (1977). The necessity of quantizing the gravitational field. Foundations of Physics, 7(1), 5168.CrossRefGoogle Scholar
Fraser, D. (2011). How to take particle physics seriously: A further defence of axiomatic quantum field theory. Studies in History and Philosophy of Modern Physics, 42(2), 126135.CrossRefGoogle Scholar
Fraser, J. D. (2016). What is quantum field theory? Idealisation, explanation and realism in high energy physics. PhD thesis, University of Leeds.Google Scholar
Fraser, J. D. (2020). The real problem with perturbative quantum field theory. British Journal for the Philosophy of Science, 71(2), 391413.CrossRefGoogle Scholar
Gies, H. & Jaeckel, J. (2004). Renormalization flow of QED. Physical Review Letters, 93(11), 110405.CrossRefGoogle ScholarPubMed
Giulini, D. (2007). Remarks on the notions of general covariance and background independence. In Stamatescu, I.-O. & Seiler, E. (Eds.), Lecture Notes in Physics, volume 721 (pp. 105120). Berlin: Springer.Google Scholar
Gomes, H. (2020). Back to parmenides. In Huggett, N., Matsubara, K., & Wüthrich, C. (Eds.), Beyond Spacetime: The Foundations of Quantum Gravity (pp. 176206). Cambridge: Cambridge University Press.Google Scholar
Goswami, K., Cao, Y., Paz-Silva, G. A., Romero, J., & White, A. G. (2020). Increasing communication capacity via superposition of order. Physical Review Research, 2, 033292.CrossRefGoogle Scholar
Großardt, A. (2021). Comment on ‘do gedankenexperiments compel quantization of gravity’. arXiv:2107.14666 [gr-qc].Google Scholar
Großardt, A. (2022). Three little paradoxes: Making sense of semiclassical gravity. AVS Quantum Science, 4(1), 010502.CrossRefGoogle Scholar
Hagar, A. (2014). Discrete or Continuous? The Quest for Fundamental Length in Modern Physics. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Harlow, D. (2016). Jerusalem lectures on black holes and quantum information. Reviews of Modern Physics, 88(1), 015002.CrossRefGoogle Scholar
Hartmann, S. (2002). On correspondence. Studies in History and Philosophy of Modern Physics, 33(1), 7994.CrossRefGoogle Scholar
Hawking, S. (1971). Gravitational radiation from colliding black holes. Physical Review Letters, 26, 1344.CrossRefGoogle Scholar
Hawking, S. (1974). Black hole explosions? Nature, 248, 3031.CrossRefGoogle Scholar
Hawking, S. (1975). Particle creation by black holes. Communications in Mathematical Physics, 43, 199220.CrossRefGoogle Scholar
Hawking, S., King, A., & McCarthy, P. (1976). A new topology for curved space-time which incorporates the causal, differential, and conformal structures. Journal of Mathematical Physics, 17(2), 174181.CrossRefGoogle Scholar
Hawking, S. & Stewart, J. (1993). Naked and thunderbolt singularities in black hole evaporation. Nuclear Physics B, 400(1–3), 393415.CrossRefGoogle Scholar
Hawking, S. W. & Ellis, G. F. (1973). The Large-Scale Structure of Space-Time. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Held, A. (2019). From particle physics to black holes: The predictive power of asymptotic safety. PhD thesis, University of Heidelberg, Heidelberg.Google Scholar
Henson, J. (2009). The causal set approach to quantum gravity. In Oriti, D. (Ed.), Approaches to Quantum Gravity: Toward a New Understanding of Space, Time and Matter (pp. 393413). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Hossenfelder, S. (2013). Minimal length scale scenarios for quantum gravity. Living Reviews in Relativity, 16, 190 (2).CrossRefGoogle ScholarPubMed
Hu, B.-L. (2009). Emergent/quantum gravity: macro/micro structures of spacetime. In Elze, H. T., Diosi, L., Fronzoni, L., Halliwell, J., & Vitiello, G. (Eds.), Fourth International Workshop Dice 2008: From Quantum Mechanics through Complexity to Spacetime: The Role of Emergent Dynamical Structures, volume 174 of Journal of Physics Conference Series (pp. 12015–12015). Bristol: IOP.Google Scholar
Huggett, N. & Callender, C. (2001). Why quantize gravity (or any other field for that matter)? Philosophy of Science, 68(3), S382S394.CrossRefGoogle Scholar
Huggett, N., Linnemann, N., & Schneider, M. D. (2023). Quantum Gravity in a Laboratory? Elements in the Foundations of Contemporary Physics. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Huggett, N. & Vistarini, T. (2015). Deriving general relativity from string theory. Philosophy of Science, 82(5), 11631174.CrossRefGoogle Scholar
Huggett, N. & Wüthrich, C. (2013). Emergent spacetime and empirical (in)coherence. Studies in History and Philosophy of Modern Physics, 44(3), 276285.CrossRefGoogle Scholar
Isham, C. (1993). Canonical quantum gravity and the problem of time. In Ibort, L. & Rodriguez, M. (Eds.), Integrable Systems, Quantum Groups, and Quantum Field Theories (pp. 157288). Dordrecht: Kluwer.CrossRefGoogle Scholar
Jackiw, R. (1999). The unreasonable effectiveness of quantum field theory. In Cao, T. (Ed.), Conceptual Foundations of Quantum Field Theory (pp. 148159). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Jackiw, R. (2000). What good are quantum field theory infinities? In Fokas, A., Grigoryan, A., Kibble, T., & Zegarlinski, B. (Eds.), Mathematical Physics 2000 (pp. 101110). Singapore: World Scientific.CrossRefGoogle Scholar
Jacobson, T. (1995). Thermodynamics of spacetime: The Einstein equation of state. Physical Review Letters, 75, 12601263.CrossRefGoogle ScholarPubMed
Jaksland, R. & Linnemann, N. S. (2020). Holography without holography: How to turn inter-representational into intra-theoretical relations in ads/cft. Studies in History and Philosophy of Modern Physics, 71, 101117.CrossRefGoogle Scholar
Kao, M. (2019). Unification beyond justification: A strategy for theory development. Synthese, 196(8), 32633278.CrossRefGoogle Scholar
Kaplan, D. B. (2005). Five lectures on effective field theory. arXiv:nucl-th/0510023.Google Scholar
Kastner, R. E. & Kauffman, S. (2018). Are dark energy and dark matter different aspects of the same physical process? Frontiers in Physics, 6(71), 14.CrossRefGoogle Scholar
Kent, A. (2018). Simple refutation of the Eppley-Hannah argument. Classical and Quantum Gravity, 35(24), 245008.CrossRefGoogle Scholar
Kiefer, C. (2007a). Quantum Gravity (2nd ed.). Oxford: Oxford University Press.CrossRefGoogle Scholar
Kiefer, C. (2007b). Why quantum gravity? In Stamatescu, I.-O. & Seiler, E. (Eds.), Approaches to Fundamental Physics, volume 721 of Lecture Notes in Physics (pp. 123130). Berlin: Springer.CrossRefGoogle Scholar
Kiefer, C. (2013). Conceptual problems in quantum gravity and quantum cosmology. ISRN Mathematical Physics, 2013, 509316.CrossRefGoogle Scholar
Kretschmann, E. (1917). Über den physikalischen sinn der relativitätspostulate: A. einsteins neue und seine ursprüngliche relativitätstheorie. Annalen der Physik, 53, 575614.Google Scholar
Kuchař, K. (1999). The problem of time in quantum geometrodynamics. In Butterfield, J. (Ed.), The Arguments of Time (pp. 169196). Oxford: Oxford University Press.Google Scholar
Kuhlmann, M. (2023). Quantum field theory. In Zalta, E. N. (Ed.), The Stanford Encyclopedia of Philosophy. Online: https://plato.stanford.edu/archives/sum2023/entries/quantum-field-theory/Google Scholar
Landau, L., Abrikosov, A., & Khalatnikov, I. (1954). The removal of infinities in quantum electrodynamics. Doklady Akademii Nauk SSSR, 14.Google Scholar
Liberati, S., Girelli, F., & Sindoni, L. (2009). Analogue models for emergent gravity. Online: https://arxiv.org/abs/0909.3834.Google Scholar
Linnemann, N. S. & Visser, M. R. (2018). Hints towards the emergent nature of gravity. Studies in History and Philosophy of Modern Physics, 64, 113.CrossRefGoogle Scholar
Loll, R. (1998). Discrete approaches to quantum gravity in four dimensions. Living Reviews in Relativity 1(13), 153.CrossRefGoogle ScholarPubMed
Loll, R. (2019). Quantum gravity from causal dynamical triangulations: A review. Classical and Quantum Gravity, 37(1), 013002.CrossRefGoogle Scholar
Loll, R., Fabiano, G., Frattulillo, D., & Wagner, F. (2022). Quantum gravity in 30 questions. arXiv:2206.06762 [hep-th].Google Scholar
Lüsher, M. & Weisz, P. (1987). Scaling laws and triviality bounds in the lattice theory: (I). one-component model in the symmetric phase. Nuclear Physics B, 290, 2560.CrossRefGoogle Scholar
Maldacena, J. (1998). The large N limit of superconformal field theories and supergravity. Advances in Theoretical and Mathematical Physics, 2, 231252.CrossRefGoogle Scholar
Manchak, J. B. & Weatherall, J. O. (2018). Paradox regained? A brief comment on maudlin on black hole information loss. Foundations of Physics, 48(6), 611627.CrossRefGoogle Scholar
Manohar, A. (1997). Effective field theories. In Latal, H. & Schweiger, W. (Eds.), Perturbative and Nonperturbative Aspects of Quantum Field Theory, volume 479 of Lecture Notes in Physics (pp. 311362). Berlin: Springer.CrossRefGoogle Scholar
Markopoulou, F. (2009a). New directions in background independent quantum gravity. In Oriti, D. (Ed.), Approaches to Quantum Gravity (pp. 129149). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Markopoulou, F. (2009b). Space does not exist, so time can. arXiv:0909.1861 [gr-qc], 19.Google Scholar
Marletto, C. & Vedral, V. (2017). Gravitationally induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity. Physical Review Letters, 119, 240402.CrossRefGoogle ScholarPubMed
Marolf, D. (2017). The black hole information problem: Past, present, and future. Reports on Progress in Physics, 80(9), 092001.CrossRefGoogle ScholarPubMed
Marolf, D. & Maxfield, H. (2020). Transcending the ensemble: Baby universes, spacetime wormholes, and the order and disorder of black hole information. Journal of High Energy Physics, 2020(8), 172.CrossRefGoogle Scholar
Mattingly, J. (2005). Is quantum gravity necessary? In Kox, A. & Eisenstaedt, J. (Eds.), The Universe of General Relativity (pp. 327338). Basel: Birkhäuser.CrossRefGoogle Scholar
Mattingly, J. (2006). Why Eppley and Hannah’s thought experiment fails. Physical Review D, 73, 062025.CrossRefGoogle Scholar
Mattingly, J. (2009). Mongrel gravity. Erkenntnis, 70(3), 379395.CrossRefGoogle Scholar
Maudlin, T. (1996). On the unification of physics. Journal of Philosophy, 93(3), 129144.CrossRefGoogle Scholar
Maudlin, T. (2012). Philosophy of Physics: Space and Time. Princeton: Princeton University Press.Google Scholar
Maudlin, T. (2017). (Information) Paradox lost. Online: https://arxiv.org/abs/1705.03541.Google Scholar
Meissner, K. A. (2004). Black-hole entropy in loop quantum gravity. Classical and Quantum Gravity, 21(22), 52455251.CrossRefGoogle Scholar
Misner, C. (1969). Absolute zero of time. Physical Review, 186(5), 13281333.CrossRefGoogle Scholar
Misner, C. W., Thorne, K. S., & Wheeler, J. A. (2017). Gravitation. Princeton: Princeton University Press.Google Scholar
Morganti, M. (2020). Fundamentality in metaphysics and the philosophy of physics. Part ii: The philosophy of physics. Philosophy Compass, 15(10), 114.Google Scholar
Morrison, M. (2000). Unifying Scientific Theories: Physical Concepts and Mathematical Structures. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Myrvold, W. C. (2003). A Bayesian account of the virtue of unification. Philosophy of Science, 70(2), pp. 399423.CrossRefGoogle Scholar
Nickles, T. (1973). Two concepts of intertheoretic reduction. The Journal of Philosophy, 70(7), 181201.CrossRefGoogle Scholar
Niedermaier, M. & Reuter, M. (2006). The asymptotic safety scenario in quantum gravity. Living Reviews in Relativity, 9(5), 1173, www.livingreviews.org/lrr–2006–5.CrossRefGoogle ScholarPubMed
Norton, J. (2003). General covariance, gauge theories and the Kretschmann objection. In Brading, K. & Castellani, E. (Eds.), Symmetries in Physics: Philosophical Reflections (pp. 110123). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Oppenheim, J. (2023). A postquantum theory of classical gravity? Physical Review X, 13, 041040.CrossRefGoogle Scholar
Oriti, D. (2009). The group field theory approach to quantum gravity. In Oriti, D. (Ed.), Approaches to Quantum Gravity: Toward a New Understanding of Space Time and Matter (pp. 310331). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Oriti, D. & Pang, X. (2021). Phantom-like dark energy from quantum gravity. Journal of Cosmology and Astroparticle Physics, 2021(12), 040.CrossRefGoogle Scholar
Overhauser, A. W. & Colella, R. (1974). Experimental test of gravitationally induced quantum interference. Physical Review Letters, 33, 12371239.CrossRefGoogle Scholar
Padmanabhan, T. (2004). Equipartition of energy in the horizon degrees of freedom and the emergence of gravity. Classical and Quantum Gravity, 21, 11291136.Google Scholar
Padmanabhan, T. (2010). Thermodynamical aspects of gravity: New insights. Reports on Progress in Physics, 73(4), 046901.CrossRefGoogle Scholar
Page, D. N. (1993). Information in black hole radiation. Physical Review Letters, 71, 37433746.CrossRefGoogle ScholarPubMed
Page, D. N. & Geilker, C. D. (1981). Indirect evidence for quantum gravity. Physical Review Letters, 47, 979982.CrossRefGoogle Scholar
Penington, G., Shenker, S. H., Stanford, D., & Yang, Z. (2022). Replica wormholes and the black hole interior. Journal of High Energy Physics 2022(205). 187.CrossRefGoogle Scholar
Penrose, R. (1965). Gravitational collapse and space-time singularities. Physical Review Letters, 14, 5759.CrossRefGoogle Scholar
Penrose, R. (1979). Singularities and time-asymmetry. In Hawking, S. & Israel, W. (Eds.), General Relativity: An Einstein Centenary Survey (pp. 581638). Cambridge: Cambridge University Press.Google Scholar
Penrose, R. (2002). Gravitational collapse: The role of general relativity. General Relativity and Gravitation, 34(7), 11411165.CrossRefGoogle Scholar
Penrose, R. (2004). The Road to Reality. London Jonathan Cape.Google Scholar
Penrose, R. (2014). On the gravitization of quantum mechanics 1: Quantum state reduction. Foundations of Physics, 44, 557575.CrossRefGoogle Scholar
Peres, A. & Terno, D. R. (2001). Hybrid classical-quantum dynamics. Physical Review A, 63, 022101.CrossRefGoogle Scholar
Pitts, J. B. (2006). Absolute objects and counterexamples: Jones-Geroch dust, Torretti constant curvature, tetrad-spinor, and scalar density. Studies in History and Philosophy of Modern Physics, 37, 347371.CrossRefGoogle Scholar
Polchinski, J. (2017). Dualities of fields and strings. Studies in History and Philosophy of Modern Physics, 59, 620.CrossRefGoogle Scholar
Pooley, O. (2010). Substantive general covariance: Another decade of dispute. In Su’arez, M., Dorato, M., & R’edei, M. (Eds.), EPSA Philosophical Issues in the Sciences: Launch of the European Philosophy of Science Association (pp. 197210). Cham: Springer.CrossRefGoogle Scholar
Pooley, O. (2017). Background independence, diffeomorphism invariance, and the meaning of coordinates. In Lehmkuhl, D., Schiemann, G., & Scholz, E. (Eds.), Towards a Theory of Spacetime Theories (pp. 105144). Basel: Birkhäuser.CrossRefGoogle Scholar
Post, H. (1971). Correspondence, invariance and heuristics: In praise of conservative induction. Studies in History and Philosophy of Science Part A, 2(3), 213255.CrossRefGoogle Scholar
Radder, H. (1991). Heuristics and the generalized correspondence principle. British Journal for the Philosophy of Science, 42, 195226.CrossRefGoogle Scholar
Read, J. (2023). Background Independence in Classical and Quantum Gravity. Oxford: Oxford University Press.CrossRefGoogle Scholar
Rickles, D. (2006). Time and structure in canonical gravity. In Rickles, D., French, S., & Saatsi, J. (Eds.), The Structural Foundations of Quantum Gravity (pp. 152196). Oxford: Oxford University Press.CrossRefGoogle Scholar
Rickles, D. (2008). Who’s afraid of background independence? In Deiks, D. (Ed.), The Ontology of Spacetime II (pp. 133152). Amsterdam: Elsevier.CrossRefGoogle Scholar
Rickles, D. (2017). Dual theories: Same but different or different but same? Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, 59, 6167.CrossRefGoogle Scholar
Rideout, D. & Zohren, S. (2006). Evidence for an entropy bound from fundamentally discrete gravity. Classical and Quantum Gravity, 23(22), 6195.CrossRefGoogle Scholar
Rosenfeld, L. (1963). On quantization of fields. Nuclear Physics, 40, 353356.CrossRefGoogle Scholar
Rovelli, C. (1996). Black hole entropy from loop quantum gravity. Physical Review Letters, 77(16), 32883291.CrossRefGoogle ScholarPubMed
Rovelli, C. (2000). Notes for a brief history of quantum gravity. In Gurzadyan, V. G., Jantzen, R. T., & Ruffini, R. (Eds.), 9th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories (MG 9) (pp. 742768).Google Scholar
Rovelli, C. (2001). Quantum spacetime: What do we know? In Callender, C. & Huggett, N. (Eds.), Physics Meets Philosophy at the Planck Scale: Contemporary Theories in Quantum Gravity (pp. 101124). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Rovelli, C. (2004). Quantum Gravity. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Rovelli, C. (2020). Space and time in loop quantum gravity. In Huggett, N., Matsubara, K., & Wüthrich, C. (Eds.), Beyond Spacetime: The Foundations of Quantum Gravity (pp. 117132). Cambridge: Cambridge University Press.Google Scholar
Rovelli, C. & Vidotto, F. (2014). Covariant Loop Quantum Gravity: An Elementary Introduction to Quantum Gravity and Spinfoam Theory. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Rydving, E., Aurell, E., & Pikovski, I. (2021). Do Gedanken experiments compel quantization of gravity? Physical Review D, 104, 086024.CrossRefGoogle Scholar
Ryu, S. & Takayanagi, T. (2006). Holographic derivation of entanglement entropy from the anti–de sitter space/conformal field theory correspondence. Physical Review Letters, 96, 181602.CrossRefGoogle ScholarPubMed
Sakharov, A. (1967). Vacuum quantum fluctuations in curved space and the theory of gravitation. Doklady Akadmii Nauk SSSR, 177, 7071.Google Scholar
Sakharov, A. D. (2000). Vacuum quantum fluctuations in curved space and the theory of gravitation. General Relativity and Gravitation, 32, 365367.CrossRefGoogle Scholar
Salimkhani, K. (2018). Quantum gravity: A dogma of unification? In Christian, A., Hommen, D., Retzlaff, N., & Schurz, G. (Eds.), Philosophy of Science: European Studies in Philosophy of Science, Vol 9. (pp. 2341). Cham: Springer.CrossRefGoogle Scholar
Salimkhani, K. (2021). Explaining unification in physics internally. Synthese, 198(6), 58615882.CrossRefGoogle Scholar
Schindler, S. (2018). Theoretical Virtues in Science: Uncovering Reality through Theory. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Smeenk, C. (2013). Philosophy of cosmology. In Batterman, R. (Ed.), Oxford Handbook of Philosophy of Physics (pp. 607652). Oxford: Oxford University Press.Google Scholar
Smeenk, C. & Wüthrich, C. (2021). Determinism and general relativity. Philosophy of Science, 88(4), 638664.CrossRefGoogle Scholar
Smolin, L. (2001). The strong and weak holographic principles. Nuclear Physics B, 601(1), 209247.CrossRefGoogle Scholar
Smolin, L. (2006). The case for background independence. In Rickles, D., French, S., & Saatsi, J. (Eds.), The Structural Foundations of Quantum Gravity (pp. 196239). Oxford: Oxford University Press.CrossRefGoogle Scholar
Smolin, L. (2013). Time Reborn: From the Crisis of Physics to the Future of the Universe. London: Allen Lane.Google Scholar
Smolin, L. (2017). Four principles for quantum gravity. In Bagla, J. & Engineer, S. (Eds.), Gravity and the Quantum, volume 187 of Fundamental Theories of Physics (pp. 427450). Cham: Springer.CrossRefGoogle Scholar
Smolin, L. (2020). Temporal relationalism. In Huggett, N., Matsubara, K., & Wüthrich, C. (Eds.), Beyond Spacetime: The Foundations of Quantum Gravity (pp. 143175). Cambridge: Cambridge University Press.Google Scholar
Stachel, J. (2006). Structure, individuality and quantum gravity. In Rickles, D. & French, S. (Eds.), The Structural Foundations of Quantum Gravity (pp. 5382). Oxford: Oxford University Press.CrossRefGoogle Scholar
Steinhauer, J. (2016). Observation of quantum Hawking radiation and its entanglement in an analogue black hole. Nature Physics, 12(10), 959965.CrossRefGoogle Scholar
Strominger, A. & Vafa, C. (1996). Microscopic origin of the Bekenstein-Hawking entropy. Physics Letters B, 379(1–4), 99104.CrossRefGoogle Scholar
Surya, S. (2019). The causal set approach to quantum gravity. Living Reviews in Relativity, 22(5), 175. https://arxiv.org/abs/1903.11544.CrossRefGoogle Scholar
Susskind, L. (1995). The world as a hologram. Journal of Mathematical Physics, 36(11), 63776396.CrossRefGoogle Scholar
Susskind, L. (2008). The Black Hole War: My Battle with Stephen Hawking to Make the World Safe for Quantum Mechanics. Boston: Little, Brown.Google Scholar
’t Hooft, G. (1993). Dimensional reduction in quantum gravity. https://arxiv.org/abs/gr-qc/9310026.Google Scholar
’t Hooft, G. & Veltman, M. (1974). One-loop divergencies in the theory of gravitation. Annales de l’IHP Physique Theorique, 20(1), 6994.Google Scholar
Thébault, K. (2019). What can we learn from analogue experiments? In Dardashti, R., Dawid, R., & Thébault, K. (Eds.), Why Trust a Theory?: Epistemology of Fundamental Physics (pp. 184201). Cambridge: Cambridge University Press.Google Scholar
Thébault, K. (2021). The problem of time. In Knox, E. & Wilson, A. (Eds.), The Routledge Companion to Philosophy of Physics (pp. 115). New York: Routledge.Google Scholar
Thébault, K. (2023). Big bang singularity resolution in quantum cosmology. Classical and Quantum Gravity, 40(5), 055007.CrossRefGoogle Scholar
Tilloy, A. (2018). Binding quantum matter and space-time, without romanticism. Foundations of Physics, 48, 15729516.CrossRefGoogle Scholar
Unruh, W. (1981). Experimental black-hole evaporation? Physical Review Letters, 46, 13511358.CrossRefGoogle Scholar
Unruh, W. G. & Wald, R. M. (2017). Information loss. Reports on Progress in Physics, 80(9), 092002.CrossRefGoogle ScholarPubMed
van Dongen, J., De Haro, S., Visser, M., & Butterfield, J. (2020). Emergence and correspondence for string theory black holes. Studies in History and Philosophy of Modern Physics, 69, 112127.CrossRefGoogle Scholar
Verlinde, E. (2011). On the origin of gravity and the laws of Newton. Journal of High Energy Physics, 2011(29), 127.CrossRefGoogle Scholar
Verlinde, E. (2017). Emergent gravity and the dark universe. SciPost Physics, 2, 016.CrossRefGoogle Scholar
Visser, M., Barceló, C., & Liberati, S. (2002). Analogue models of and for gravity. General Relativity and Gravitation, 34(10), 17191734. 3rd Australasian Conference on General Relativity and Graviattion Jul 11–13, 2001 Perth, Australia.CrossRefGoogle Scholar
Volovik, G. (2003). The Universe in a Helium Droplet. Oxford: Oxford University Press.Google Scholar
Wald, R. M. (1994). Quantum Field Theory in Curved Spacetime and Black Hole Thermodynamics. Chicago: University of Chicago Press.Google Scholar
Wald, R. M. (2001). The thermodynamics of black holes. Living Reviews in Relativity, 4(1), 6.CrossRefGoogle ScholarPubMed
Wall, A. C. (2009). Ten proofs of the generalized second law. Journal of High Energy Physics, 2009(06), 021.CrossRefGoogle Scholar
Wallace, D. (2006). In defence of naivete: The conceptual status of Lagrangian quantum field theory. Synthese, 151(1), 33.CrossRefGoogle Scholar
Wallace, D. (2011). Taking particle physics seriously: A critique of the algebraic approach to quantum field theory. Studies in History and Philosophy of Modern Physics, 42(2), 116125.CrossRefGoogle Scholar
Wallace, D. (2018a). The case for black hole thermodynamics part i: Phenomenological thermodynamics. Studies in History and Philosophy of Modern Physics, 64, 5267.CrossRefGoogle Scholar
Wallace, D. (2018b). The case for black hole thermodynamics part ii: Statistical mechanics. Studies in History and Philosophy of Modern Physics, 66(C), 103117.CrossRefGoogle Scholar
Wallace, D. (2020). Why black hole information loss is paradoxical. In Huggett, N., Matsubara, K., & Wüthrich, C. (Eds.), Beyond Spacetime: The Foundations of Quantum Gravity (pp. 209236). Cambridge: Cambridge University Press.Google Scholar
Wallace, D. (2022). Quantum gravity at low energies. Studies in History and Philosophy of Science, 94, 3146.CrossRefGoogle ScholarPubMed
Weinberg, S. (1979). Ultraviolet divergencies in quantum theories of gravitation. In Hawking, S. & Israel, W. (Eds.), General Relativity, an Einstein Centenary Survey (pp. 790831). Cambridge: Cambridge University Press.Google Scholar
Weinberg, S. (1995). The Quantum Theory of Fields, Vol. I (Foundations). Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Weinberg, S. (2009). Effective field theory, past and future. arXiv:hep-th/0908.1964v3.Google Scholar
Weinfurtner, S., Tedford, E. W., Penrice, M. C., Unruh, W. G., & Lawrence, G. A. (2013). Classical aspects of Hawking radiation verified in analogue gravity experiment. In Faccio, D., Belgiorno, F., Cacciatori, S., Gorini, V., Liberati, S., & Moschella, U. (Eds.), Analogue Gravity Phenomenology (pp. 167180). Cham: Springer.CrossRefGoogle Scholar
Weinstein, S. & Rickles, D. (2021). Quantum gravity. The Stanford Encyclopedia of Philosophy, https://plato.stanford.edu/archives/fall2021/entries/quantum–gravity/.Google Scholar
Wheeler, J. (2000). Geons, Black Holes and Quantum Foam. London: W.W. Norton.Google Scholar
Williams, P. (2021). Renormalization group methods. In Knox, E. & Wilson, A. (Eds.), The Routledge Companion to Philosophy of Physics (pp. 130). New York: Routledge.Google Scholar
Williams, R. (2006). Discrete quantum gravity. Journal of Physics: Conference Series, 33(1), 38.Google Scholar
Witten, E. (1998). Anti-de Sitter space, thermal phase transition, and confinement in gauge theories. Advances in Theoretical and Mathematical Physics, 2, 505532.CrossRefGoogle Scholar
Wüthrich, C. (2005). To quantize or not to quantize: Fact and folklore in quantum gravity. Philosophy of Science, 72, 777788.CrossRefGoogle Scholar
Zee, A. (2010). Quantum Field Theory in a Nutshell (Second ed.). Princeton: Princeton University Press.Google Scholar
Zeh, H. (2011). Feynmans interpretation of quantum theory. The European Physical Journal H, 36, 6374.CrossRefGoogle Scholar
Zwiebach, B. (2009). A First Course in String Theory (Second ed.). Cambridge: Cambridge University Press.CrossRefGoogle Scholar

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