Passage Times for Unbiased Polymer Translocation through a Narrow Pore

We study the translocation process of a polymer in the absence of external fields for various pore diameters $b$ and membrane thickness $L$. The polymer performs Rouse and reptation dynamics. The mean translocation time $<\tau_t>$ that the polymer needs to escape from a cell, and the mean dwell time $<\tau_d>$ that the polymer spends in the pore during the translocation process, obey scaling relations in terms of the polymer length $N$, $L$ and $b/R_g$, where $R_g$ is the radius of gyration for the polymer. We explain these relations using simple arguments based on polymer dynamics and the equilibrium properties of polymers.