English

On the relation between Euclidean and Lorentzian 2D quantum gravity

High Energy Physics - Theory 2009-10-31 v1 General Relativity and Quantum Cosmology High Energy Physics - Lattice

Abstract

Starting from 2D Euclidean quantum gravity, we show that one recovers 2D Lorentzian quantum gravity by removing all baby universes. Using a peeling procedure to decompose the discrete, triangulated geometries along a one-dimensional path, we explicitly associate with each Euclidean space-time a (generalized) Lorentzian space-time. This motivates a map between the parameter spaces of the two theories, under which their propagators get identified. In two dimensions, Lorentzian quantum gravity can therefore be viewed as a ``renormalized'' version of Euclidean quantum gravity.

Keywords

Cite

@article{arxiv.hep-th/9912267,
  title  = {On the relation between Euclidean and Lorentzian 2D quantum gravity},
  author = {J. Ambjorn and J. Correia and C. Kristjansen and R. Loll},
  journal= {arXiv preprint arXiv:hep-th/9912267},
  year   = {2009}
}

Comments

12 pages, 2 figures

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