Structural Issues in Quantum Gravity

Abstract

A discursive, non-technical, analysis is made of some of the basic issues that arise in almost any approach to quantum gravity, and of how these issues stand in relation to recent developments in the field. Specific topics include the applicability of the conceptual and mathematical structures of both classical general relativity and standard quantum theory. This discussion is preceded by a short history of the last twenty-five years of research in quantum gravity, and concludes with speculations on what a future theory might look like.

42 pages, latex, no figures. Writeup of GR14 plenary lecture

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Cited by in corpus (58)

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• Black Hole Entropy from Loop Quantum Gravity
• ``Sum over Surfaces'' form of Loop Quantum Gravity
• An interferometric gravitational wave detector as a quantum-gravity apparatus
• Threshold effects and Planck scale Lorentz violation: combined constraints from high energy astrophysics
• Some remarks on high derivative quantum gravity
• Geometry Eigenvalues and Scalar Product from Recoupling Theory in Loop Quantum Gravity
• A Uniqueness Theorem for Constraint Quantization
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• Interacting classical and quantum ensembles
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• Gravity-wave interferometers as probes of a low-energy effective quantum gravity
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• (Quantum) Space-Time as a Statistical Geometry of Fuzzy Lumps and the Connection with Random Metric Spaces
• Quantum evolution in spacetime foam
• Physics with nonperturbative quantum gravity: radiation from a quantum black hole
• Movement and Fluctuations of the Vacuum
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• Proposal of a second generation of quantum-gravity-motivated Lorentz-symmetry tests: sensitivity to effects suppressed quadratically by the Planck scale
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• (Quantum) Space-Time as a Statistical Geometry of Lumps in Random Networks
• Quantum Gravity Phenomenology and Lorentz Violation
• BOOST -- A Satellite Mission to Test Lorentz Invariance Using High-Performance Optical Frequency References
• The emergence of Special and Doubly Special Relativity
• Nonassociative geometry: Towards discrete structure of spacetime
• Effective Field Theory of Gravity, Reduction of Couplings and the Renormalization Group
• Quantum Hamiltonian for gravitational collapse
• Pregeometric Concepts on Graphs and Cellular Networks as Possible Models of Space-Time at the Planck-Scale
• Loop Quantum Gravity and Black Hole Physics
• Laboratory bounds on Lorentz symmetry violation in low energy neutrino physics
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• A Class of Exact Solutions of the Wheeler -- De Witt Equation
• Pregeometric modelling of the spacetime phenomenology
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• A perspective on Quantum Gravity Phenomenology
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• Wheeler-De Witt equation and AdS/CFT correspondence
• Quantum Potential and Quantum Gravity
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• Quantum Gravity
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• Five Dimensional Dynamical Triangulations
• L'universo emergente della gravita' quantistica
• Building Blocks in Turaev-Viro Theory
• Topological discretization of bosonic strings