Dynamics of the constrained polymer collapse

The dynamics of polymer collapse with a fixed distance between endpoints is studied analytically and numerically by the Nosé-Hoover algorithm. We find that at the pearling stage of the collapse the number of pearls decays as $t^{-1/2}$ leading to anomalously long collapse time. To understand the effect of Stokes drag we reduced the problem of long-polymer-chain collapse to the one-dimensional diffusion-limited coalescence of particles with the mass-dependent mobility. In this case the number of pearls decays slower, as $t^{-3/7}$.