Random Groups are not $n$-Cubulated

Zachary Munro

Published 2024-03-13Version 1

A group $G$ has $F\mathcal C_n$ if every action on a $n$-dimensional $\mathrm{CAT}(0)$ cube complex has a global fixed point. This provides a natural stratification between Serre's $FA$ and Kazhdan's $(T)$. For every $n$, we show that random groups in the plain words density model have $F\mathcal C_n$ with overwhelming probability. The same result holds for random groups in the reduced words density model assuming there are sufficiently many generators. These are the first examples of cubulated hyperbolic groups with $F\mathcal C_n$ for $n$ arbitrarily large.