# Emergent diffeomorphism invariance in a discrete loop quantum gravity model

@article{Gambini2009EmergentDI, title={Emergent diffeomorphism invariance in a discrete loop quantum gravity model}, author={Rodolfo Gambini and Jorge Pullin}, journal={Classical and Quantum Gravity}, year={2009}, volume={26}, pages={035002} }

Several approaches to the dynamics of loop quantum gravity involve discretizing the equations of motion. The resulting discrete theories are known to be problematic since the first-class algebra of constraints of the continuum theory becomes second class upon discretization. If one treats the second-class constraints properly, the resulting theories have very different dynamics and number of degrees of freedom than those of the continuum theory. It is therefore questionable how these theories…

## 12 Citations

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- 2011

Diffeomorphism symmetry, the fundamental invariance of general relativity, is generically broken under discretization. After discussing the meaning and implications of diffeomorphism symmetry in the…

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The Cosmic Fabric model of gravity that was previously introduced by Tenev and Horstemeyer [T. G. Tenev and M. F. Horstemeyer, Int. J. Mod. Phys. D 27 (2018) 1850083; Rep. Adv. Phys. Sci. 2 (2018)…

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We consider the notion of improved and perfect actions within Regge calculus. These actions are constructed in such a way that they - although being defined on a triangulation - reproduce the…

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