Large Strebel Graphs and (3,2) Liouville CFT

  • Séverin Charbonnier
  • Bertrand Eynard
  • François David


2D quantum gravity is the idea that a set of discretized surfaces (called map, a graph on a surface), equipped with a graph measure, converges in the large size limit (large number of faces) to a conformal field theory (CFT), and in the simplest case to the simplest CFT known as pure gravity, also known as the gravity dressed (3,2) minimal model. Here, we consider the set of planar Strebel graphs (planar trivalent metric graphs) with fixed perimeter faces, with the measure product of Lebesgue measure of all edge lengths, submitted to the perimeter constraints. We prove that expectation values of a large class of observables indeed converge toward the CFT amplitudes of the (3,2) minimal model.


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BE was supported by the ERC Starting Grant no. 335739 “Quantum fields and knot homologies” funded by the European Research Council under the European Union’s Seventh Framework Programme. BE is also partly supported by the ANR Grant Quantact: ANR-16-CE40-0017. We thank P. di Francesco for his interest and useful conversations.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Séverin Charbonnier
    • 1
  • Bertrand Eynard
    • 1
    • 2
  • François David
    • 1
  1. 1.Institut de physique théorique, CEA, CNRSUniversité Paris SaclayGif-sur-YvetteFrance
  2. 2.Centre de Recherches MathématiquesUniversité de MontréalMontréalCanada

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