# 3+1 spinfoam model of quantum gravity with spacelike and timelike components

@article{Perez200031SM, title={3+1 spinfoam model of quantum gravity with spacelike and timelike components}, author={Alejandro Perez and Carlo Rovelli}, journal={Physical Review D}, year={2000}, volume={64}, pages={064002} }

We present a spin foam formulation of Lorentzian quantum general relativity. The theory is based on a simple generalization of a Euclidean model defined in terms of a field theory over a group. The model is an extension of a recently introduced Lorentzian model, in which both timelike and spacelike components are included. The spin foams in the model, corresponding to quantized 4-geometries, carry a natural nonperturbative local causal structure induced by the geometry of the algebra of the…

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