# Consistently Solving the Simplicity Constraints for Spinfoam Quantum Gravity

@article{Livine2007ConsistentlyST, title={Consistently Solving the Simplicity Constraints for Spinfoam Quantum Gravity}, author={Etera R. Livine and Simone Speziale}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2007} }

We give an independent derivation of the Engle-Pereira-Rovelli spinfoam model for quantum gravity which recently appeared in [arXiv:0705.2388]. Using the coherent state techniques introduced earlier in [arXiv:0705.0674], we show that the EPR model realizes a consistent imposition of the simplicity constraints implementing general relativity from a topological BF theory.

## 177 Citations

A Short and Subjective Introduction to the Spinfoam Framework for Quantum Gravity

- Physics
- 2011

This is my Th\`ese d'Habilitation (HDR) on the topic of spinfoam models for quantum gravity, which I presented in l'Ecole Normale Sup\'erieure de Lyon on december 16 2010. The spinfoam framework is a…

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We find a nontrivial regime of spinfoam quantum gravity that reproduces classical Einstein equations. This is the double scaling limit of small Immirzi parameter (gamma), large spins (j) with…

Divergences in spinfoam quantum gravity

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The spinfoam formalism is an attempt to define the dynamics of loop quantum gravity in an explicitly Lorentz covariant way. It defines transition amplitudes for spinnetwork states of the canonical…

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This work applies the recently developed U(N) framework for SU(2) intertwiners to the issue of imposing the simplicity constraints to spin network states and proposes a set of U( N) coherent states that solves all the simplicity constraint weakly for an arbitrary Immirzi parameter.

Amplitudes in the Spin Foam Approach to Quantum Gravity

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In this thesis, we study a Spin Foam model for 4D Riemannian quantum gravity, and propose a new way of imposing the simplicity constraints that uses the recently developed holomorphic representation.…

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- 2008

We generalize a model recently proposed for Euclidean quantum gravity to the case of Lorentzian signature. The main features of the Euclidean model are preserved in the Lorentzian one. In particular,…

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Bernard d’Espagnat. We welcome today Carlo Rovelli, who has kindly accepted to speak to us about his book Quantum Gravity. Carlo has already participated several times in our discussions;…

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It's widely recognized that general relativity emerges if we impose invariance under local translations and local Lorentz transformations. In the same manner supergravity arises when we impose…

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Starting from the reformulation of the classical phase space of Loop Quantum Gravity in terms of spinor variables and spinor networks, we build coherent spin network states and show how to use them…

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