Survivor-conditioned renewal laws and observable bounds for open intermittent maps

Abstract

Recent numerical computations and stochastic modeling by Brevitt and Klages suggest that introducing a hole in a Pomeau--Manneville map can suppress survivor-conditioned Lyapunov stretching. We prove a deterministic renewal theorem which explains this phenomenon and its observable-level generalizations. For an open intermittent map induced on a base away from the neutral fixed point, we describe the asymptotic distribution of the number of completed survivor returns to the base, conditioned on survival up to time $t$. The limiting law is expressed in terms of the killed induced transfer operator; for the conditionally invariant density of the killed induced system it is geometric. We then prove two reward results for additive observables. A reward domination theorem gives bounded survivor-conditioned Birkhoff sums, while a stronger final-tail asymptotic gives convergence to a finite limit. For generalized Pomeau--Manneville maps, bounded observables satisfying $\lvert \psi(x) \rvert \leq C x^{\gamma}$ near the neutral fixed point and a mild variation condition satisfy the domination hypotheses. When the neutral branch and final tails satisfy the corresponding regularity assumptions, asymptotically regular observables satisfy the convergence hypotheses. In particular, $\psi=\log\lvert f' \rvert$ gives bounded survivor-conditioned Lyapunov stretching for the generalized class; under these additional regularity assumptions, it converges. Under an additional entropy-domination assumption, we also derive a zero entropy-rate consequence for survivor return-length names and record the complementary linear growth of stretching when the hole contains a neighborhood of the neutral fixed point.