English

Solving the Simplest Theory of Quantum Gravity

High Energy Physics - Theory 2013-02-18 v2 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

Abstract

We solve what is quite likely the simplest model of quantum gravity, the worldsheet theory of an infinitely long, free bosonic string in Minkowski space. Contrary to naive expectations, this theory is non-trivial. We illustrate this by constructing its exact factorizable S-matrix. Despite its simplicity, the theory exhibits many of the salient features expected from more mature quantum gravity models, including the absence of local off-shell observables, a minimal length, a maximum achievable (Hagedorn) temperature, as well as (integrable relatives of) black holes. All these properties follow from the exact S-matrix. We show that the complete finite volume spectrum can be reconstructed analytically from this S-matrix with the help of the thermodynamic Bethe Ansatz. We argue that considered as a UV complete relativistic two-dimensional quantum field theory the model exhibits a new type of renormalization group flow behavior, "asymptotic fragility". Asymptotically fragile flows do not originate from a UV fixed point.

Keywords

Cite

@article{arxiv.1205.6805,
  title  = {Solving the Simplest Theory of Quantum Gravity},
  author = {Sergei Dubovsky and Raphael Flauger and Victor Gorbenko},
  journal= {arXiv preprint arXiv:1205.6805},
  year   = {2013}
}

Comments

32+4 pages, 1 figure, v2: typos fixed, published version

R2 v1 2026-06-21T21:12:01.986Z