On the Dimension of Random Simplicial Complexes
Kinga Nagy
TL;DR
This work analyzes the extreme-dimensional functional of random geometric simplicial complexes built on Poisson point processes, linking dimension to both clique numbers and scan statistics. It develops a unified, Poisson-based framework to obtain expectations, large deviations principles, two-point concentration in sparse regimes, and precise distribution results in the dense regime for both Vietoris-Rips and Čech complexes. The results reveal regime-dependent behavior: sparse settings exhibit sharp two-point concentration while dense regimes exhibit Poisson-type distributional limits, with a special Gumbel limit in 1D. Overall, the paper advances understanding of extreme-valued functionals on random geometric complexes and provides tools for related scan-statistics analyses.
Abstract
The dimension of random simplicial complexes (defined as the maximal dimension among all faces) is a natural extreme value associated with the complex, and is closely related to other functionals defined by a maximum, such as the clique number of geometric graphs or scan statistics. We extend existing results in the binomial point process case to the Poisson setting in sparse graphs, give new ones about expectations and large deviation principles in all regimes, as well as give a first precise distribution result in the dense case.
