# Quantum gravity as sum over spacetimes

@article{Ambjorn2010QuantumGA, title={Quantum gravity as sum over spacetimes}, author={Jan Ambjorn and Jerzy Jurkiewicz and R Loll}, journal={Lecture Notes in Physics}, year={2010}, volume={807}, pages={59-124} }

A major unsolved problem in theoretical physics is to reconcile the classical theory of general relativity with quantum mechanics. These lectures will deal with an attempt to describe quantum gravity as a path integral over geometries. Such an approach has to be non-perturbative since gravity is a non-renormalizable quantum field theory when the dimension of spacetime is four.

## 71 Citations

Quantum Einstein gravity

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- 2012

We give a pedagogical introduction to the basic ideas and concepts of the Asymptotic Safety program in quantum Einstein gravity. Using the continuum approach based upon the effective average action,…

Quantum Gravity in Plebanski Formulation

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We present a theory of four-dimensional quantum gravity with massive gravitons which may be essentially renormalizable. In Plebanski formulation of general relativity in which the tetrads, the…

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Causal dynamical triangulations (CDT ) represent a lattice regularization of the sum over spacetime histories, providing us with a nonperturbative formulation of quantum gravity. The ultraviolet…

Lattice Quantum Gravity - an Update

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We advocate lattice methods as the tool of choice to constructively define a backgroundindependent theory of Lorentzian quantum gravity and explore its physical properties in the Planckian regime.…

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- Physics, Philosophy
- 2009

I give a pedagogical explanation of what it is about quantization that makes general relativity go from being a nearly perfect classical theory to a very problematic quantum one. I also explain why…

F eb 2 01 3 Quantum Gravity via Causal Dynamical Triangulations

- Physics
- 2011

“Causal Dynamical Triangulations” (CDT) represent a lattice regularization of the sum over spacetime histories, providing us with a non-perturbative formulation of quantum gravity. The ultraviolet…

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