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MINISUPERSPACE MODEL FOR REVISED CANONICAL QUANTUM GRAVITY [PDF]
International Journal of Modern Physics D, 2004 We present a reformulation of the canonical quantization of gravity, as referred to the minisuperspace; the new approach is based on fixing a Gaussian (or synchronous) reference frame and then quantizing the system via the reconstruction of a suitable constraint; then the quantum dynamics is re-stated in a generic coordinates system and it becomes ...
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On 2D quantum gravity coupled to a σ-model [PDF]
Nuclear Physics B - Proceedings Supplements, 1996 This contribution is a review of the method of isomonodromic quantization of dimensionally reduced gravity. Our approach is based on the complete separation of variables in the isomonodromic sector of the model and the related ``two-time" Hamiltonian structure.
Korotkin, D., Nicolai, H., Samtleben, H.
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UNITARY MATRIX MODELS AND 2D QUANTUM GRAVITY [PDF]
Modern Physics Letters A, 1992 The KdV and modified KdV integrable hierarchies are shown to be different descriptions of the same 2D gravitational system — open-closed string theory. Non-perturbative solutions of the multicritical unitary matrix models map to non-singular solutions of the 'renormalization group' equation for the string susceptibility, [Formula: see text].
Dalley, S. +3 more
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A Matrix Model for Flat Space Quantum Gravity
Journal of High Energy Physics, 2023 Abstract We take a step towards the non-perturbative description of a two-dimensional dilaton-gravity theory which has a vanishing cosmological constant and contains black holes. This is done in terms of a double-scaled Hermitian random matrix model which non-perturbatively computes the partition function for the asymptotic Bondi ...
Kar, Arjun +3 more
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Quantum singularities in a model of f(R) gravity [PDF]
The European Physical Journal C, 2012 The formation of a naked singularity in a model of f(R) gravity having as source a linear electromagnetic field is considered in view of quantum mechanics. Quantum test fields obeying the Klein-Gordon, Dirac and Maxwell equations are used to probe the classical timelike naked singularity developed at r=0.
Gürtuğ, Özay +2 more
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Testing a (Stringy) Model of Quantum Gravity [PDF]
, 2001 I discuss a specific model of space-time foam, inspired by the modern non-perturbative approach to string theory (D-branes). The model views our world as a three brane, intersecting with D-particles that represent stringy quantum gravity effects, which can be real or virtual.
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Spin foam models of Riemannian quantum gravity [PDF]
Classical and Quantum Gravity, 2002 Using numerical calculations, we compare three versions of the Barrett-Crane model of 4-dimensional Riemannian quantum gravity. In the version with face and edge amplitudes as described by De Pietri, Freidel, Krasnov, and Rovelli, we show the partition function diverges very rapidly for many triangulated 4-manifolds.
Baez, John C. +3 more
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Matrix quantization of gravitational edge modes
Journal of High Energy Physics, 2023 Gravitational subsystems with boundaries carry the action of an infinite-dimensional symmetry algebra, with potentially profound implications for the quantum theory of gravity.
William Donnelly +3 more
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Spikes and spines in 4D Lorentzian simplicial quantum gravity
Journal of High Energy PhysicsSimplicial approaches to quantum gravity such as quantum Regge calculus and spin foams include configurations where bulk edges can become arbitrarily large while the boundary edges are kept small.
Johanna Borissova +3 more
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Topology induced first-order phase transitions in lattice quantum gravity
Journal of High Energy Physics, 2022 Causal Dynamical Triangulations (CDT) is a lattice formulation of quantum gravity, suitable for Monte-Carlo simulations which have been used to study the phase diagram of the model.
J. Ambjorn +3 more
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