Visibility to infinity in the hyperbolic plane, despite obstacles
| dc.creator | Benjamini, Itai | |
| dc.creator | Jonasson, Johan | |
| dc.creator | Schramm, Oded | |
| dc.creator | Tykesson, Johan | |
| dc.date | 2008-07-21 | |
| dc.date.accessioned | 2026-07-07T09:51:52Z | |
| dc.date.available | 2026-07-07T09:51:52Z | |
| dc.description | Suppose that $Z$ is a random closed subset of the hyperbolic plane $\H^2$, whose law is invariant under isometries of $\H^2$. We prove that if the probability that $Z$ contains a fixed ball of radius 1 is larger than some universal constant $p<1$, then there is positive probability that $Z$ contains (bi-infinite) lines. We then consider a family of random sets in $\H^2$ that satisfy some additional natural assumptions. An example of such a set is the covered region in the Poisson Boolean model. Let $f(r)$ be the probability that a line segment of length $r$ is contained in such a set $Z$. We show that if $f(r)$ decays fast enough, then there are almost surely no lines in $Z$. We also show that if the decay of $f(r)$ is not too fast, then there are almost surely lines in $Z$. In the case of the Poisson Boolean model with balls of fixed radius $R$ we characterize the critical intensity for the almost sure existence of lines in the covered region by an integral equation. We also determine when there are lines in the complement of a Poisson process on the Grassmannian of lines in $\H^2$. | |
| dc.identifier | https://arxiv.org/abs/0807.3308 | |
| dc.identifier | http://arxiv.org/abs/0807.3308 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/165395 | |
| dc.subject | Probability | |
| dc.subject | Mathematical Physics | |
| dc.subject | 82B43; 82B27; 82B21 | |
| dc.title | Visibility to infinity in the hyperbolic plane, despite obstacles | |
| dc.type | text |