Abstract:
Let {Zi,i=0,1,2,...} be a critical branching process in
random environment and the variance σ2 of a step of the
associated random walk is finite and positive. Consider a sequence of
branching processes Z(n,x)={Z(n,x)i,i=0,1,...}, where Z(n,x)i={Zi|Z0=mn(x)} and logmn(x)∼σx√n as n→∞ for some x>0.
Three limit theorems are proved: on the extinction time of the process Z(n,x), on the properties of a normalized process constructed
by Z(n,x), and on the normalized logarithm of the process.