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Debabrata Panja Institute for Theoretical Physics, Universiteit van Amsterdam Passage Times for Unbiased Polymer Translocation through a Narrow Pore Cond-mat/0509577; submitted to Phys. Rev. Lett. Transport of molecules across membranes is an essential mechanism for life processes. These molecules are often long, and the pores in the membranes are too narrow for the molecules to pass through as a single unit. In such circumstances, the molecules have to squeeze --- i.e., translocate --- themselves through the pores. DNA, RNA and proteins are such naturally occuring long molecules in a variety of biological processes. Translocation is a complicated process in living organisms --- the presence of chaperon molecules, pH, chemical potential gradients, and assisting molecular motors strongly influence its dynamics. Consequently, the translocation process has been empirically studied in great variety in biological literature. Study of translocation as a biophysical process is more recent. Herein, the polymer is simplified to a sequentially connected string of N monomers as it passes through a narrow pore on a membrane. The quantities of interest are the typical time scale for the polymer to leave a confining cell (the "escape of a polymer from a vesicle" time scale), and the typical time scale the polymer spends in the pore (the "dwell" time scale) as a function of N and other parameters like membrane thickness, membrane adsorption, electrochemical potential gradient, etc. In this talk, I will present recent results for 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/Rg, where Rg is the radius of gyration for the polymer. We have explained these scaling relations using simple arguments based on polymer dynamics and the equilibrium properties of polymers.