Simplicial Euclidean and Lorentzian Quantum Gravity

  title={Simplicial Euclidean and Lorentzian Quantum Gravity},
  author={Jan Ambjorn},
  journal={arXiv: General Relativity and Quantum Cosmology},
  • J. Ambjorn
  • Published 9 January 2002
  • Mathematics
  • arXiv: General Relativity and Quantum Cosmology
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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