# Quantum gravity in terms of topological observables

@article{Freidel2005QuantumGI, title={Quantum gravity in terms of topological observables}, author={Laurent Freidel and Artem Starodubtsev}, journal={arXiv: High Energy Physics - Theory}, year={2005} }

We recast the action principle of four dimensional General Relativity so that it becomes amenable for perturbation theory which doesn't break general covariance. The coupling constant becomes dimensionless (G_{Newton} \Lambda) and extremely small 10^{-120}. We give an expression for the generating functional of perturbation theory. We show that the partition function of quantum General Relativity can be expressed as an expectation value of a certain topologically invariant observable. This sets…

## 24 Citations

### Quantum Gravity as a Deformed Topological Quantum Field Theory

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It is known that the Einstein-Hilbert action with a positive cosmological constant can be represented as a perturbation of the SO(4, 1) BF theory by a symmetry-breaking term quadratic in the B field.…

### Effective particle kinematics from Quantum Gravity

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Particles propagating in de Sitter spacetime can be described by the topological BF SO(4; 1) theory coupled to point charges. Gravitational interaction between them can be introduced by adding to the…

### Lessons from toy-models for the dynamics of loop quantum gravity

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We review some approaches to the Hamiltonian dynamics of (loop) quantum gravity, the main issues being the regularization of the Hamiltonian and the continuum limit. First, Thiemann's definition of…

### On the expansion of a quantum field theory around a topological sector

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The idea of treating quantum general relativistic theories in a perturbative expansion around a topological theory has recently received attention, in the quantum gravity literature. We investigate…

### Hidden quantum gravity in 4D Feynman diagrams: emergence of spin foams

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We show how Feynman amplitudes of standard quantum field theory on flat and homogeneous space can naturally be recast as the evaluation of observables for a specific spin foam model, which provides…

### Topological methods in quantum gravity

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The main technical problem with background independent approaches to quantum gravity is inapplicability of standard quantum field theory methods. New methods are needed which would be adapted to the…

### Perturbative quantum gravity with the Immirzi parameter

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We study perturbative quantum gravity in the first-order tetrad formalism. The lowest order action corresponds to Einstein-Cartan plus a parity-odd term, and is known in the literature as the Holst…

### An Action for higher spin gauge theory in four dimensions

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- 2011

An action principle is presented for Vasiliev's Bosonic higher spin gauge theory in four spacetime dimensions. The action is of the form of a broken topological field theory, and arises by an…

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