# Simplicial Euclidean and Lorentzian Quantum Gravity

@article{Ambjorn2002SimplicialEA, title={Simplicial Euclidean and Lorentzian Quantum Gravity}, author={Jan Ambjorn}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2002} }

One can try to define the theory of quantum gravity as the sum over geometries. In two dimensions the sum over {\it Euclidean} geometries can be performed constructively by the method of {\it dynamical triangulations}. One can define a {\it proper-time} propagator. This propagator can be used to calculate generalized Hartle-Hawking amplitudes and it can be used to understand the the fractal structure of {\it quantum geometry}. In higher dimensions the philosophy of defining the quantum theory…

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