{ "id": "1311.5847", "version": "v2", "published": "2013-11-22T19:23:11.000Z", "updated": "2015-02-15T20:43:28.000Z", "title": "Liouville Brownian motion at criticality", "authors": [ "Rémi Rhodes", "Vincent Vargas" ], "comment": "52 pages", "categories": [ "math.PR", "math-ph", "math.MP" ], "abstract": "In this paper, we construct the Brownian motion of Liouville Quantum Gravity with central charge $c=1$ (more precisely we restrict to the corresponding free field theory). Liouville quantum gravity with $c=1$ corresponds to two-dimensional string theory and is the conjectural scaling limit of large planar maps weighted with a $O(n=2)$ loop model or a $Q=4$-state Potts model embedded in a two dimensional surface in a conformal manner. Following \\cite{GRV1}, we start by constructing the critical LBM from one fixed point $x\\in\\mathbb{R}^2$ (or $x\\in\\S^2$), which amounts to changing the speed of a standard planar Brownian motion depending on the local behaviour of the critical Liouville measure $M'(dx)=-X(x)e^{2X(x)}\\,dx$ (where $X$ is a Gaussian Free Field, say on $\\mathbb{S}^2$). Extending this construction simultaneously to all points in $\\mathbb{R}^2$ requires a fine analysis of the potential properties of the measure $M'$. This allows us to construct a strong Markov process with continuous sample paths living on the support of $M'$, namely a dense set of Hausdorff dimension $0$. We finally construct the associated Liouville semigroup, resolvent, Green function, heat kernel and Dirichlet form. In passing, we extend to quite a general setting the construction of the critical Gaussian multiplicative chaos that was initiated in \\cite{Rnew7,Rnew12} and also establish new capacity estimates for the critical Gaussian multiplicative chaos.", "revisions": [ { "version": "v1", "updated": "2013-11-22T19:23:11.000Z", "abstract": "In this paper, we construct the Brownian motion of Liouville Quantum gravity when the underlying conformal field theory has a $c=1$ central charge. Liouville quantum gravity with $c=1$ corresponds to two-dimensional string theory and is the conjectural scaling limit of large planar maps weighted with a $O(n=2)$ loop model or a $Q=4$-state Potts model embedded in a two dimensional surface in a conformal manner. Following \\cite{GRV1}, we start by constructing the critical LBM from one fixed point $x\\in\\mathbb{R}^2$ (or $x\\in\\mathbb{S}^2$), which amounts to changing the speed of a standard planar Brownian motion depending on the local behaviour of the critical Liouville measure $M'(dx)=-X(x)e^{2X(x)}\\,dx$ (where $X$ is a Gaussian Free Field on $\\mathbb{R}^2$ or $\\mathbb{S}^2$). Extending this construction simultaneously to all points in $\\mathbb{R}^2$ requires a fine analysis of the potential properties of the measure $M'$. This allows us to construct a strong Markov process with continuous sample paths living on the support of $M'$, namely a dense set of Hausdorff dimension $0$. We finally construct the Liouville semigroup, resolvent, Green function, heat kernel and Dirichlet form of (critical) Liouville quantum gravity with a $c=1$ central charge. In passing, we extend to quite a general setting the construction of the critical Gaussian multiplicative chaos that was initiated in \\cite{Rnew7,Rnew12}.", "journal": null, "doi": null }, { "version": "v2", "updated": "2015-02-15T20:43:28.000Z" } ], "analyses": { "subjects": [ "60J65", "81T40" ], "keywords": [ "liouville brownian motion", "liouville quantum gravity", "central charge", "criticality", "strong markov process" ], "note": { "typesetting": "TeX", "pages": 52, "language": "en", "license": "arXiv", "status": "editable", "inspire": 1265710, "adsabs": "2013arXiv1311.5847R" } } }