Spin foam models for quantum gravity from lattice path integrals - General Relativity and Quantum CosmologyReport as inadecuate




Spin foam models for quantum gravity from lattice path integrals - General Relativity and Quantum Cosmology - Download this document for free, or read online. Document in PDF available to download.

Abstract: Spin foam models for quantum gravity are derived from lattice path integrals.The setting involves variables from both lattice BF theory and Regge calculus.The action consists in a Regge action, which depends on areas, dihedral anglesand includes the Immirzi parameter.
In addition, a measure is inserted toensure a consistent gluing of simplices, so that the amplitude is dominated byconfigurations which satisfy the parallel transport relations.
We explicitlycompute the path integral as a sum over spin foams for a generic measure.
TheFreidel-Krasnov and Engle-Pereira-Rovelli models correspond to a special choiceof gluing.
In this case, the equations of motion describe genuine geometries,where the constraints of area-angle Regge calculus are satisfied.
Furthermore,the Immirzi parameter drops out of the on-shell action, and stationarity withrespect to area variations requires spacetime geometry to be flat.



Author: Valentin Bonzom

Source: https://arxiv.org/



DOWNLOAD PDF




Related documents