R. Cerf, F. Manzo
The threshold regime of finite volume bootstrap percolation.
(49K, LaTeX)

ABSTRACT.  We prove that the threshold regime for 
bootstrap percolation in a $d$-dimensional 
box of diameter $L$ with parameters $p$ and $\ell$, 
where $3 \le \ell \le d$, 
is $L \sim \eexp{(\ell -1)} (C p^{-1/(d-\ell +1)})$, 
where $\eexp{(\ell -1)}$ is the exponential iterated $\ell-1 $ times 
and $C$ is bounded from above and from below by two positive 
constants depending on $d$, $\ell$ only.