• Corpus ID: 251468172

Light ray fluctuation and lattice refinement of simplicial quantum gravity

@inproceedings{Jia2022LightRF,
  title={Light ray fluctuation and lattice refinement of simplicial quantum gravity},
  author={Ding Jia},
  year={2022}
}
In several approaches of non-perturbative quantum gravity, a major outstanding problem is to obtain results valid at the infinite lattice refinement limit. Working with Lorentzian simplicial quantum gravity, we compute light ray fluctuation probabilities in 3D and 4D across different lattices. In a simplified refined box model with the Einstein-Hilbert action, numerical results show that lattice refinement does not simply suppress or simply enhance light ray fluctuations, but actually drives very wide… 
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A non-perturbative study on the quantum fluctuations of light ray propagation through a quantum region of spacetime is long overdue. Within the theory of Lorentzian simplicial quantum gravity, we

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    Classical and Quantum Gravity
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Evaluating gravitational path integrals in the Lorentzian has been a long-standing challenge due to the numerical sign problem. We show that this challenge can be overcome in simplicial quantum

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