English

Bounds for distances and geodesic dimension in Liouville first passage percolation

Probability 2019-06-25 v3 Mathematical Physics math.MP

Abstract

For ξ0\xi \geq 0, Liouville first passage percolation (LFPP) is the random metric on εZ2\varepsilon \mathbb Z^2 obtained by weighting each vertex by εeξhε(z)\varepsilon e^{\xi h_\varepsilon(z)}, where hε(z)h_\varepsilon(z) is the average of the whole-plane Gaussian free field hh over the circle Bε(z)\partial B_\varepsilon(z). Ding and Gwynne (2018) showed that for γ(0,2)\gamma \in (0,2), LFPP with parameter ξ=γ/dγ\xi = \gamma/d_\gamma is related to γ\gamma-Liouville quantum gravity (LQG), where dγd_\gamma is the γ\gamma-LQG dimension exponent. For ξ>2/d2\xi > 2/d_2, LFPP is instead expected to be related to LQG with central charge greater than 1. We prove several estimates for LFPP distances for general ξ0\xi\geq 0. For ξ2/d2\xi\leq 2/d_2, this leads to new bounds for dγd_\gamma which improve on the best previously known upper (resp.\ lower) bounds for dγd_\gamma in the case when γ>8/3\gamma > \sqrt{8/3} (resp.\ γ(0.4981,8/3)\gamma \in (0.4981, \sqrt{8/3})). These bounds are consistent with the Watabiki (1993) prediction for dγd_\gamma. However, for ξ>1/3\xi > 1/\sqrt 3 (or equivalently for LQG with central charge larger than 17) our bounds are inconsistent with the analytic continuation of Watabiki's prediction to the ξ>2/d2\xi >2/d_2 regime. We also obtain an upper bound for the Euclidean dimension of LFPP geodesics.

Keywords

Cite

@article{arxiv.1903.09561,
  title  = {Bounds for distances and geodesic dimension in Liouville first passage percolation},
  author = {Ewain Gwynne and Joshua Pfeffer},
  journal= {arXiv preprint arXiv:1903.09561},
  year   = {2019}
}

Comments

12 pages, 2 figures; final version, to appear in ECP