English

Upper large deviations for maximal flows through a tilted cylinder

Probability 2009-07-06 v1

Abstract

We consider the standard first passage percolation model in \ZZd\ZZ^d for d2d\geq 2 and we study the maximal flow from the upper half part to the lower half part (respectively from the top to the bottom) of a cylinder whose basis is a hyperrectangle of sidelength proportional to nn and whose height is h(n)h(n) for a certain height function hh. We denote this maximal flow by τn\tau_n (respectively ϕn\phi_n). We emphasize the fact that the cylinder may be tilted. We look at the probability that these flows, rescaled by the surface of the basis of the cylinder, are greater than ν(v)+\eps\nu(\vec{v})+\eps for some positive \eps\eps, where ν(v)\nu(\vec{v}) is the almost sure limit of the rescaled variable τn\tau_n when nn goes to infinity. On one hand, we prove that the speed of decay of this probability in the case of the variable τn\tau_n depends on the tail of the distribution of the capacities of the edges: it can decays exponentially fast with nd1n^{d-1}, or with nd1min(n,h(n))n^{d-1} \min(n,h(n)), or at an intermediate regime. On the other hand, we prove that this probability in the case of the variable ϕn\phi_n decays exponentially fast with the volume of the cylinder as soon as the law of the capacity of the edges admits one exponential moment; the importance of this result is however limited by the fact that ν(v)\nu(\vec{v}) is not in general the almost sure limit of the rescaled maximal flow ϕn\phi_n, but it is the case at least when the height h(n)h(n) of the cylinder is negligible compared to nn.

Keywords

Cite

@article{arxiv.0907.0614,
  title  = {Upper large deviations for maximal flows through a tilted cylinder},
  author = {Marie Theret},
  journal= {arXiv preprint arXiv:0907.0614},
  year   = {2009}
}

Comments

14 pages, 4 figures

R2 v1 2026-06-21T13:21:05.225Z